Nonbovine Ruminations

Thoughts on Bitcasa

2011-09-15T03:18:00.001-05:00

Bitcasa has been getting a lot of attention in my Google Plus circles the past week or so; I suspect this is because it was in the running for TechCrunch's Disrupt prize (but ultimately lost to something called "Shaker", which appears to me to be some sort of virtual bar simulation). Bitcasa claims to offer "infinite" storage on desktop computers for a fixed monthly fee. I've yet to see any solid technical information on how they're doing this, but it seems to me that they're planning to do this by storing your data in the cloud and using the local hard drive as a cache.

There's nothing earthshattering about this; I set up Tivoli Hierarchical Storage Manager to store infrequently used files on lower-priority storage media (either cheap NAS arrays or tape) four years ago with my last employer, and the technology was fairly mature then. Putting the HSM server, data stores, or both in the cloud was possible even then and should be even more so now that cloud services are far more mature than they were then. So while there are obviously issues to sort out, this isn't a big reach technically.

More interesting to me is how they plan to provide "infinite" storage. Given the promise of infinite storage, most users will never delete anything; my experience is that users don't delete files until they run out of space, and if they really do have "infinite" storage that won't ever happen. The rule of thumb I recall from storage planning 101 is that storage requirements double every 18 months. According to Matthew Komorowski, the cost of storage drops by half every 14 months, so their cost to provide that doubled storage should slowly decline over time, but that margin is fairly thin and may not be sufficient to cover the exponentially growing complexity of their storage infrastructure over time. They'll also have to cope with ever-increasing amounts of data transit, but I can't find good information just now on the trend there, in part because transit pricing is still very complicated.

More interesting to me is that Bitcasa appears to be claiming that they will use deduplication to reduce the amount of data transferred from clients to the server. This is, itself, not surprising. The surprising thing is that they also claim that they will be using interclient deduplication; that is, if you have a file that another client has already transferred, they won't actually transfer the file. I think they're overselling the savings from interclient deduplication, though. I may not be typical, but the bulk of the file data on my systems seems to fall into a few categories: camera raws for the photos I've taken; datasets I've compiled for various bulk data analyses (e.g. census data, topographic elevation maps, the FCC licensee database); virtual machine images; and savefiles from various games I play. The camera raw files (over 10,000 photographs at around 10 megs each) are obviously unique to me, and as I rarely share the raws their opportunity to leverage deduplication gain there is essentially nil. As to the datasets, they themselves are duplicative (most of them are downloaded from government sources), of course, but the derived files that I've created from the source datasets are unique to me and are often larger than the source data. So, again, only limited gain opportunity there. Most of my virtual machine images are unique to me, as I've built them from the bottom up myself. And obviously the saved games are unique to me. If I were to sign up my laptop and its 220 GB hard drive (actually larger than that but I haven't gotten around to resizing the main partition from when I reimaged the drive onto a newer, larger drive after a drive crash a couple months ago, so Windows still thinks it's a 220 GB drive) onto Bitcasa, they'd probably end up having to serve me somewhere around 170 to 200 GB of storage, depending mainly on how well it compresses. (Much of the data on my machine is already compressed.)

Even my music (what there is of it; I keep a fairly small collection of about 20 gigabytes) doesn't dedup well. I know, I've tried to dedup my music catalog several times over the past decade plus and my experience is that "identical" songs are often not identical at the bit level; the song might be the same but the metatags differ in some manner that makes them not bit-compatible. Or the songs might be compressed with different bit rates or even different algorithms; I have several albums that I've ripped as many as five times over the years with different rippers. Even if you rip the same song twice from the same disc with the same settings on the same ripper it still might end up with a different bitstream, if the disc has a wobbly bit on it.

If Bitcasa assumes that most of its clients will be "typical" computer users, most of whose data is "stuff downloaded from the Internet", then I suppose they can expect significant deduplication gain, especially for videos, music, and especially for executables and libraries (nearly everyone on a given version of Windows will have the same NTOSKRNL.EXE, for example. although in general OS files cannot be made nonresident anyway without affecting the ability of the computer to boot). The problem I think they're going to run into is that many of their early adopters are not going to be like that. Instead, they're going to be people like us: content creators far more than content consumers, whose computers are all filled to the brim with stuff we've created ourselves out of nothing, unlike anything else out there in the universe.

Then there's the whole issue of getting that 220 GB of data on my machine to their servers. It took my computer nearly 40 days to complete its initial Carbonite image, and that's without backing up any of the executables. I have some large files that I keep around for fairly infrequent use; if Bitcasa decides to offline one of those and I end up needing it, I might be facing a fairly long stall while it fetches the file from their server. Or, if I'm using the computer off the net (something I often do), then I'm hosed, and if I'm on a tether (which is also fairly frequent) then I could be facing a download of a gig file (or larger) over Verizon 3G at about 200 kbps. Good thing Verizon gives me unlimited 3G data!

I also wonder how Bitcasa will interact with applications that do random access to files, such as database apps and virtual machine hosts. I use both of these on a fairly regular basis, and I think it might get ugly if Bitcasa wants to offline one of my VHDs or MDFs (or even my Outlook OST or my Quickbooks company file). If they are planning to use reparse points on Windows the way Tivoli HSM does, files that will need to be accessed randomly, or which need advanced locking semantics, will have to be fully demigrated before they can be used at all.

In addition to all this, the use of cryptographic hashes to detect duplicates is risky. There's always the chance of hash collision. Yes, I know, the odds of that are very small with even a decent sized hash. But an event with even very low odds will happen with some regularity if there are enough chancves for it to occur, which is why we can detect the 21cm ultra-fine hydrogen spin transition at 1420.405752 MHz: this transition occurs with a probability of something like one in a billion, but we can detect it fairly easily because there are billions upon billions of hydrogen atoms in the universe. With enough clients, eventually there's going to be a hash collision, which will ultimately result in replacing one customer's file with some totally different file belonging to some other customer. Worse yet, this event is undetectible to the service provider. (Kudos to the folks at spideroak for pointing this out, along with other security and legal concerns that interclient deduplication presents.)

So while I think the idea is interesting, I think they're going to face some pretty serious issues in both the short term (customer experience not matching customer expectation, especially with respect to broadband speed limitations) and long term (storage costs growing faster than they anticipate). Ought to be interesting to see how it plays out, though. I think it's virtually certain that they'll drop the "infinite" before too very long.

(Disclaimers: Large portions of this post were previously posted by me on Google Plus. I am not affiliated with any of the entities named in this post.)

Aaron Swartz v. JSTOR

2011-07-19T14:30:00.001-05:00

So the big noise on G+ today (at least in my circles) is all about Aaron Swartz' arrest for hacking into MIT's network and downloading over 4 million journal articles from JSTOR. Demand Progress, the nonprofit that Aaron is connected to, in a masterful bit of spin, is alleging that he has been "bizarrely" charged with "downloading too many journal articles". This would be true insofar as "too many" in the circumstances in which he did it would have been zero, if you are to believe the indictment. The problem isn't so much that he downloaded "too many" articles, but instead that (as alleged in the indictment) he used several different false IDs in his attempts to do so, did so as such a rate that it created problems for JSTOR's service, took several affirmative steps to evade MIT's and JSTOR's attempts to stop him (at which point he knew, or should have known, he had exceeded his access), and eventually resorted to sneaking into restricted areas at MIT in order to facilitate the process further before finally being caught in the act by MIT police.

Of course, many of the people on Google+ are insisting that this is about copyright (it's not) and that Aaron's actions strike a great blow for the freedom of information (they don't) and that this might even take down JSTOR (it won't). It is fairly clear that Aaron's actions are for one of two purposes: either he was collecting data for the same sort of mass analysis of journal articles that he did back in 2008 (which purportedly involved some 400,000 journal articles), or else he was planning to release the downloaded articles onto the Internet through a file sharing service (as is alleged in the indictment). Both of these would be fairly noble causes; I find it rather unlikely that Aaron's intent here was venal.

However, if his intent was noble, that doesn't explain the spin from Demand Progress. If this is civil disobedience, then they should be doing what other protest organizations have done in similar situations: admit what they did, say why they did it, and demand a public outcry against whatever was so wrong that it justified breaking the law, while at the same time standing prepared to accept the consequences of having broken the law. However, DP's PR statement doesn't do that. It instead calls the prosecution "bizarre" and clearly intends to whitewash Aaron's use of falsified identity information, increasingly determined attempts to evade MIT's and JSTOR's security, and eventually repeated criminal trespasses to MIT's grounds, in order to accomplish his goals. That, to me, is not mindset of civil disobedience, but instead the mindset of the criminal attempting to avoid responsibility for his crime.

So, to Aaron: dude, boner move. There are better ways to do this sort thing that don't involve skulking around in MIT's basement peering through the ventholes of your bike helmet. To Aaron's supporters: please don't make this about copyright. It's about Aaron not thinking clearly about his goals and means. I'd have a comment for JSTOR, too, but I really don't know what to say. Someone has to collate, digitize, and store these documents, and to expect them to do it for free seems silly. Someone has to pay for it. (But see also JSTOR's comment on the indictment.)

Information may want to be free, but data centers are not free. Theft of computing services is not a "victimless crime", and fundamentally that's what Aaron did here. If his access really was for "research", then I'd like to know if he attempted to negotiate with JSTOR for the access that he needed, or if he merely assumed that they wouldn't let him have it. I'd be a lot more sympathetic if he made an effort and was rebuffed.

In any case, I imagine Aaron will end up like poor ol' Mitnick: barred from using computers for some time, barred from the MIT campus forever, and slapped with a huge fine and a felony conviction or two. And he's not even 25 yet.

Also, if anybody finds the security camera images of him sneaking around using his bike helmet to hide his face, please let me know.

Weinergate, or the dangers of public WiFi

2011-05-30T09:09:00.001-05:00

So the news is all atwitter today over what has been dubbed "Weinergate" by at least some in the media, relating to New York Congressman Anthony Weiner allegedly tweeting a picture of an erection to a college student in Seattle. Anthony Weiner has claimed that his Twitter account was hacked in order to do this, a claim which conservatives are denying. This post is about the credibility of Weiner's claim, and the hidden danger of using public unencrypted WiFi to access password-protected services.

Weiner is a pretty aggressive user of social media services, from what I've seen, and he seems to be using them himself (rather than delegating that to a social media consultant). He probably uses a smartphone of some sort to post his tweets. Like many other people, he likely uses public WiFi access points when they're available, as such services are typically faster than the 3G network when they are available. The problem with this, though, is that when you access a password-protected service like Twitter or Facebook, your device sends your password to the service provider in order to authenticate your session. By default, that password is sent using what is called "basic authentication", which sends the password without any encryption; the password is sent in the clear, and anyone who can overhear the exchange will be able to see, and more importantly, capture both the username and password. The key here is the "anyone who can overhear the exchange": the only thing protecting your Twitter password is the physical security of the medium being used to send your login request to Twitter.

This isn't that terribly much of a problem if the computer is connected to the internet via a wired connection: the unencrypted passwords will typically be exposed only to the chain of internet service providers between the user's computer and the social network. Now, there are certainly risks here, but in general ISPs do not collect intelligence about their customers and share that intelligence with third parties (other than the US government, that is); I've never heard of a social media account being hacked through password collection at an ISP. Basically, in the wired case the physical security of the medium is fairly good, and so the risk is low.

The same is true if you're using 3G/4G wireless. All the various digital cellular protocols used for cellular wireless use transport encryption, meaning it would be phenomenally difficult to intercept and successfully recover the content of a login request sent via cellular wireless.

However, things get a lot shakier when we start talking about WiFi. WiFi is notorious for its history of poor transport security; the original WEP security provided with early WiFi systems is flawed and can be cracked with an ordinary computer in a matter of hundreds (sometimes tens) of seconds. There are newer standards that alleviate this in various ways and the newer WPA and WPA2 encryption algorithms are probably sufficiently as secure as the underlying wired networks they're connected to. But the real danger here is unencrypted public WiFi. Here there is no transport security at all: everything you send, and everything you receive, is sent with no encryption at all. And since it's being sent over a radio medium, that means anyone with a compatible radio receiver can listen in to the entire conversation. The long and the short of it is that if you log into Facebook, Twitter, or most other social networking services over a public unencrypted WiFi service, you are sharing your login details, including your password, with everyone in radio range of your device.

There are widely available tools that are specifically designed to sniff WiFi sessions for social media passwords, and it's a fair bet that at any event where a public-access unencrypted WiFi is available, someone will be running one of these tools. And if you're a prominent public political figure who is known to use social media from a mobile device, someone like, say, Anthony Weiner, it's reasonable to assume that your political enemies will send someone to follow you about with one of these tools for the sole purpose of trying to capture your passwords. In short, you got pwned by firesheep, Anthony.

So what's the solution here? First, don't ever use a public unencrypted WiFi service to send sensitive information, including a password, without taking additional steps to protect your security. The simplest is to not use public WiFi. With many devices, this is the only safe choice: my Droid will automatically attempt to log on to all of its various social networking connections (to collect updates) as soon as it detects that it has Internet access. For mobile devices, therefore, one should rely only on cellular access and on password-protected WiFi sources that you already trust. This means, for example, turning off the option to automatically connect to any public WiFi that your device might detect.

Another option, which isn't really available on smartphones but would be on notebooks, is to install a browser add-on that forces social media sessions to be conducted via HTTPS instead of HTTP. Most of Google's properties already offer this; Google forces all login sessions to be sent via HTTPS, meaning the password will be encrypted in transit. I think Yahoo is also doing this. There is a plugin available for Firefox that forces Facebook, Twitter, and selected other sites to always use HTTPS encryption, to protect you from password grabbing, and I would recommend the use of such tools. I use one called Force-TLS on my own notebook.

A more aggressive option, and one that would have likely be a good choice for Congressman Weiner, would be to set up a VPN endpoint at your home or business (or at a public VPN endpoint service like PublicVPN) and force all your public Internet access through that client. This also ensures that all your Internet activity is encrypted by the VPN client before it leaves your device, ensuring that you won't be vulnerable.

And, of course, we should all pressure Facebook, Twitter, and other services to do as Google has done and redesign their services to avoid this vulnerability in the first place.

To bring it back to Weinergate, I personally find Weiner's claim, that his password was hacked, fairly credible. At least one conservative has poopooed the notion that someone could have hacked both his Twitter password and his Yfrog password at the same time, but in reality that's fairly likely with a WiFi password capture tool; all they have to do is observe him using both Twitter and Yfrog in the same session, which is a fairly common usage since most usage of Yfrog is on referral from Twitter. If one of his political opponents has been chasing him about following him with a password sniffer it's entirely possible that they have a large collection of his passwords. Not to mention that there's the real risk that he used the same password on both; while Weiner is a smart guy that doesn't mean he's necessarily an expert on Internet security, and even smart guys fall prey to that fairly common mistake.

Oregon tax on electric cars

2011-04-26T10:59:00.001-05:00

So Oregon has decided that it's unfair for drivers of electric cars to avoid paying road use taxes and is proposing a special tax on electric cars to make up for this "inequity". This post will discuss why this is stupid, and why Oregon should resist the urge to implement this tax.

The federal government and, as far as I know, all of the states, impose excise taxes on gasoline. While in most cases these taxes are treated as general revenue and can be used for any purpose, there is the notion that they should be used to pay for road maintenance and construction, on the idea that the more one uses the roads the more one should pay for their upkeep, and gasoline usage is a fairly good proxy for road usage. Diesel fuel is taxed similarly, but one can also buy "exempt" diesel for use in off-road applications, such as running farm equipment or generators. The current federal gas tax is 18.4 cents per gallon; state gas taxes vary, but in Oregon (the state in question) is 30 cents a gallon. Thus, a car that gets 30 miles per gallon (which is slightly better than the 27.5 mpg fleet average required by CAFE) will pay one cent per mile in Oregon gas tax. The proposed tax on electric vehicles is one to two cents per mile, which suggests that Oregon believes that electric car owners should pay more than their fair share for road usage, itself an interesting statement.

The proposal, however, is misguided for at least four reasons. First, all-electric vehicles are, at this time, almost universally passenger cars, and usually small ones at that. Passengers cars present almost no wear and tear on roads; virtually all wear and tear on roads is the result of usage by trucks, or the result of weather (or other natural processes like earthquakes or landslides). So while cars represent the majority of users they do not cause the majority of wear and tear, and thus upkeep; that burden therefore ought to fall more heavily on larger vehicle operators. Diesel taxes are sometimes, but not universally, higher than gas taxes, reflecting the fact that most heavy vehicles run on diesel fuel; in Oregon diesel is also taxed at 30 cents per gallon. In any case, there is no reason why the tax burden on electric passenger cars should be greater than that of gasoline-powered passenger car of similar weight and performance.

Second, there are solid public policy reasons to abate road-use taxes on electric vehicles. Electric vehicles do not produce point pollution, and in the Pacific Northwest especially where a great deal of the electricity is produced by hydroelectric power, produce no pollution at all. The reduction in point pollution production is itself sufficient grounds to give a tax abatement to operators of such vehicles. Certainly imposing a tax burden equal to or greater than that imposed by pollution-generating gasoline-powered vehicles would be nonsensical, because it would tend to discourage consumers from making a choice that we would prefer them to make.

Third, the amount of tax that would be collected would not exceed the cost of collecting the tax. The typical electric vehicle that would be subjected to this tax has a range of about 80 miles. A vehicle driven 80 miles each day, five days a week, fifty weeks a year would travel around 20,000 miles, and be subject to a tax of between $120 and $400 a year (depending on tax rate). Most vehicles will be driven far less, with correspondingly lower tax revenue. Oregon estimates that there will be approximately 5000 vehicles subject to the tax in 2014 when it takes effect, generating probably somewhere between $200,000 and $500,000 in annual revenue. That means that the Oregon Department of Revenue has to implement this tax with fewer than ten full-time equivalents, or it will end up being revenue-negative.

Fourth, a miles-driven basis for taxation raises issues for taxing out-of-state vehicles operated in Oregon and Oregon-titled vehicles outside of Oregon. The use of gasoline taxes as a proxy for road usage relies in part on the fact that in most cases, motor vehicle fuel is used fairly proximal to its point of purchase. So while there is a discrepancy between state of purchase and state of use, in most cases it probably evens out in the end (although there are lots of exceptions, especially for communities near state lines where one state has a significantly lower tax rate than the other). However, if some road users are taxed by proxy and others for actual usage, that creates an inequitable basis for taxation. Arguably, if Oregon is going to tax electric vehicle owners for miles driven in Oregon, then it needs to do so as well for gasoline-powered vehicle owners as well. This then generates additional problems of crediting vehicle owners for miles driven outside of Oregon without being overly intrusive on owner privacy (the pilot program from some years ago used GPS technology, but that amounts to tracking the movements of anyone who owns a vehicle subject to this tax, and that just won't fly), and also on taxing out of state vehicles that are operated within Oregon. Finally, plugin hybrids risk double taxation under this plan, since they might well pay both a miles-driven tax and a gasoline excise tax. Replacing one tax inequity with several new ones is not an improvement. In this case it switches the burden of the inequity from an option disfavored in public policy (polluting) to one favored in public policy (not polluting), which is just stupid.

Fundamentally, I think Oregon's action in this regard is misguided. I'm sure they're seeing declining fuel tax revenues; the recession has resulted in people driving far less, and virtually every state has reported declining fuel tax revenues as a result. Also, I imagine the oil companies have been astroturfing the notion that it's unfair for electric vehicles (which they view as a huge threat) to be allowed to avoid taxation like this, and I'm sure the idea to tax electric vehicles has been driven at least in part by their public policy management agencies. Finally, the idea of implementing a special tax on a consumer choice that we bend over backwards elsewhere in public policy to encourage is just moronic. I just don't see the point of creating an entirely novel tax infrastructure to collect what would be at most a half million dollars of revenue on an activity that likely saves the state at least that much in costs elsewhere anyway. In fact, for me the fact that the revenue collected is not likely to exceed the cost of collecting it leads me to believe that the real purpose of this tax is to discourage people from owning electric vehicles, and that tells me that the real reason for the tax is to protect the oil and gas industry in Oregon. What's the real motivation here? (Keep in mind that Oregon is also one of only two states that prohibits self-serve gasoline stations.)

No, Oregon, this is a dumb idea. Don't put barriers in the way of progress, just because the oil companies want you to. Say no to HB 2328.

An example of when to use VLANs, and the danger of closet monkeys

2011-04-06T09:38:00.001-05:00

I wrote a couple days ago about abusing VLANs. Just yesterday I had an occasion to use VLANs for a client, so I thought I'd write about that. There's also a "closet monkey" anecdote in here, as a cautionary tale as to why you shouldn't let outside techs into your network closets or server rooms unsupervised.

This client recently entered into an arrangement with a hosted provider for voice-over-IP telephony. The arrangement this provider offers installs Polycom SIP phones at the business location, along with a gateway device that is installed on the network to aggregate the SIP devices and trunk calls back to the service provider's facility. (As far as I can tell, call control is handled at the provider's facility, but that's not important right now.) This gateway device, in addition to its VoIP functionality, is capable of acting as a fairly generic NAT appliance. This particular provider's installer apparently uses a playbook for installing these devices that involves removing any gateway device that customer already has and replacing it by their device. This device also provides DHCP with a variety of specialized options preloaded for the benefit of the phones, including, apparently, their own DNS servers, which their system makes some use of in some way that wasn't clearly explained to me.

However, in my client's case this didn't quite work out. My client has Windows 2008 Small Business Server running at that location, with Active Directory in use. The SBS server provides both DNS and DHCP for the network; DHCP was not being provided by the existing gateway devices (a Watchguard firewall). So when they ripped the Watchguard out of the network and installed their gateway device, the DHCP server in their device conflicted with the DHCP server in the SBS server; fortunately, the gateway detected this and shut off its DHCP server. This resulted in the phones not getting all the extra DHCP options that they needed for optimal operation, nor did they have access to the provider's DNS servers.

It was about this point that they called me, to ask if there was some way to change the DNS for the network to point to their servers instead of the local Windows server. Of course, that's not acceptable; this client is using Active Directory, and in an AD environment it is absolutely nonnegotiable that all AD clients must use the Active Directory DNS servers, at least for all zones that describe the AD forest. I was, however, willing to configure the Windows server to use the provider's DNS servers as first-level forwarders, which would mean that any query not answerable by the zones defined in that server would be forwarded to the provider for resolution. (It is fairly rare for people to understand how DNS works; perhaps I'll blog about this in the future.)

So, while on the conference call, I went to remote into the client's site, in order to make the necessary changes to the DNS service. And here's where I ran into more problems. The VPN would not connect, for the fairly simple reason that they had disconnected the Watchguard firewall that was being used as the VPN endpoint. (It was at this point that I and my client discovered that they had done this.) Further discussion and inspection determined that they had disconnected the Watchguard from the WAN side, and I suspected also from the LAN side, although that wasn't confirmed until the next day when I went on site. This was clearly unacceptable. Remote access via that device is essential to this client's business operations as well as to my ability to provide them remote support; also, this client runs a FTP server at this location which is used for communications with a couple of business partners, which was obviously also made unavailable as a result of this change. It's possible that I might have been able to configure this new gateway device to provide comparable services; however, my main complaint is that this provider removed a gateway device without discussion or even notification as part of their install routine. There's a reason more experienced network engineers like myself refer to such people as "closet monkeys". When I was a full-time systems person I generally refused to let anyone outside the organization into my server room or network closets without direct supervision; it's incidents like this that explain why.

Anyhow, during the 45-minute conference call two nights ago, after it became apparent that this installers had rather significantly broken my client's network and that I would have to go in to fix it, we then discussed how to make all this work in harmony. Apparently their device doesn't like operating behind another firewall, and I suspect it will also not play well in router-on-a-stick mode. We could have arranged that using the Watchguard's "optional" network, but that would have required them to break from their playbook and negotiate with me, and getting a closet monkey to negotiate with the customer is usually impossible. However, they had actually done me a favor in disguise. This client has Comcast business cable modem service using an SMC cable modem. This modem supports transparent bridging but cannot be configured to do it by the customer; turning that on can only be done from the provider end. When I migrated the client from DSL to cable modem, about a month ago, I would have preferred transparent bridging but didn't want to deal with calling Comcast to set it up, so I set up a double NAT solution instead by configuring the modem to map each public IP to a RFC 1918 IP, and then using those mapped IPs at the firewall's WAN interface. This solution was less than ideal, in my opinion, but was working, so I left it alone. However, the installers for this system had apparently contacted Comcast and had the modem switched to transparent bridging to better support their device. A blessing in disguise. Anyhow, this meant that the cable modem was now presenting five public IP addresses (five of the six usable addresses of a /29 network, the sixth having been allocated to the cable modem itself) on its LAN ports, but their gateway device only needed one; I could use one of the others for the client's firewall and restore remote access, and another for the FTP site; only minor reconfiguration of the firewall would be needed, once it had been reconnected, of course. The only question remaining was how to run both devices in parallel, without conflict.

Here's where VLANs come in. The strategy here is to have one VLAN for the PCs (and printers and servers and other devices) and another, entirely separate VLAN, for the phones. This not only allows my client to continue using their firewall device, which has been set up for their specific business needs, but also allows the provider's edge device to serve all the special DHCP options to the phones that are required to make the phones work correctly, and allow the phones to get the DNS servers that the provider wants them to use, without interfering with the needs of the active directory environment. It's truly as if there were two entirely separate LANs. (There isn't even any routing between the two VLANs; while I could have set that up, there was no benefit to doing so.)

The only remaining issue was in how to get the phones to live on their VLAN without having to run additional cabling. The phones in question, as I mentioned, are Polycom SIP devices. Like most VoIP phones, they have passthrough Ethernet ports so that you don't have to install additional cabling to install them; you just plug the PC into the phone and the phone into the wall where the PC was plugged in before. In addition, like most VoIP phones, they support 802.1q tagging for VoIP traffic, which means the phone's traffic is tagged with 802.1q tags that allow a suitably capable switch to segregate the traffic for the phones from the traffic from the passthrough port (which is sent untagged). The provider wasn't able to advise me on how to set the phones up to do this, but I was able to figure it out anyway, having set up VoIP telephony systems before. Furthermore, Polycom has fairly decent documentation for its phones available on the net; all that was required was the addition of a special DHCP option to the Windows DHCP server, and I was able to fairly quickly find out what option was needed and what syntax these phones needed for that. This allowed the phones to operate on the voice VLAN while still using the same cable for passthrough data traffic to any device connected to the phone's passthrough port.

So, I defined a second VLAN on the client's switches, and set up all but three ports on the switches as "untagged 1 tagged 101" (1 being the data VLAN and 101 being the voice VLAN). The phones, when they boot, execute a DHCP discover on the data (untagged) VLAN. The Windows server responds with an IP address offer that includes the DHCP tag that tells the phone to switch to VLAN 101. The phone then rejects the DHCP offer and switches its VoIP interface to the tagged VLAN and sends another DHCP discover on the voice VLAN, which is responded to by the VoIP gateway device with all of the settings that are particular to the voice network. Other devices on the data network (such as workstations) just ignore this DHCP option and proceed as usual. Two of the ports that were not set up this way were set up as "untagged 101"; one of these was connected to the edge device (so that the edge device would not get 802.1q tags that it wasn't set up to deal with) and the other I used for configuration and troubleshooting access during the process. The final remaining port goes to an unmanaged gigabit switch that interconnects the client's servers; that switch is not 802.1q aware and thus should also not received tagged packets, and in any case no device on that switch needs to see voice traffic.

In this case, VLANs were key to solving this client's problem. The traffic segregation and quality of service wasn't really an issue; this client's network is small enough that it's unlikely that there'd be capacity issues. In this case segregation was mandated by the need to have distinct DHCP environments. In theory I could have used a DHCP server that used the requesting client's client ID or MAC address to serve different DHCP options, but such features are not standard in most DHCP servers. The VLAN solution was simpler.

One of the problems small businesses often face (often without knowing it) is that there's a bevy of solution providers out there that are offering what amount to turnkey solutions, and in most cases the solution is being deployed by people who are only trained to deal with a small subset of the possible environments they'll run into. Sometimes that'll work out OK, but really if you want a good result you need someone involved who is looking out for your needs, concerns, and interests. You just can't count on someone else's technician to do that. The solution they provide has been optimized for their needs, not necessarily for yours.

Scary ways to abuse VLANs

2011-03-31T00:37:00.001-05:00

I ran across this article the other day (after someone at the Spiceworks Forums posted a link to it). It made me cringe, repeatedly, to read it. This post will address why this other article is so wrong, and why you should not do what this guy suggests.

The key to understanding how to approach this lies in understanding what a "broadcast domain" is. A broadcast domain is the set of devices all of whom will receive a broadcast sent by any other member of that set. Normally, every device connected to a standard LAN switch will be in the same broadcast domain; in short, switches define broadcast domains. Every device connected to the same LAN is a member of the same broadcast domain.

What VLANs allow one to do is treat a switch as if it were multiple independent switches, coexisting in the same box. The switch is told to group its ports, some to one virtual switch, others to another. The end result is to have multiple LANs (virtual LANs, or VLANs) coexisting on the same hardware. You could get the same result by buying multiple switches, one for each independent LAN. VLANs just let you do this with fewer switches. That's all. (There's some added complexity when you start talking about trunking and about layer 3 switching, but neither of these is essential to understanding what a VLAN is.)

The author's definition of a VLAN (Virtual LAN) as a "technology that enables dividing a physical network into logical segments at Layer 2" is, I suppose, not entirely inaccurate; however, it's less than useful to understanding what a VLAN is. The problem this author has is that he's viewing VLANs as a partitioning of a physical network. But that's not the right approach. While VLANs have this effect, that's not the way to understand them. It's far better to think of VLANs as a way for multiple LANs—that is, multiple broadcast domains—to independently coexist in the same hardware, much the way that virtualization hypervisors allow multiple computers to independently coexist on the same hardware.

A few lines down from that is another flat out wrong statement. VLANs are not used to "join physically separate LANs or LAN segments into a single logical LAN". You cannot do that with VLANs alone; doing this (if for some reason you wanted to) is the role of a bridge or a tunnel—or just a cable between two switches. You might use a VLAN in the course of setting up a bridge or tunnel, but VLANs don't allow you to do this on their own.

The discussion on page two about the use of VLANs to control broadcast traffic is fundamentally correct; this is one of the major reasons for separating a network into multiple broadcast domains. The statement "Small LANs are typically equivalent to a single broadcast domain" really illustrates the fundamental mistake this author made: a LAN is, by definition, a broadcast domain, and so a small LAN would necessarily also be a broadcast domain. There's also some discussion about IP multicasts that is all entirely incorrect and should be just ignored. The reason IP multicasting is disabled on most consumer routers is because the routers aren't smart enough to handle them correctly; it's got nothing to do with bandwith consumption. In actuality, the proper configuration of IP multicasting in switches and routers that support it fully reduces, rather than increases, bandwidth use, and most large networks will turn these functions on to maximize bandwidth utilization.

And a little bit later we have another killer doozy statement: "VLANs can be configured on separate subnets". Indeed, not only can they be, but in fact they pretty much have to be, assuming you're using VLANs properly. Since each VLAN is a separate broadcast domain, and each separate broadcast domain needs its own subnet, each VLAN (in a properly constructed network) will have its own, distinct, subnet. The author here gets away with breaking this rule only because the switch he's using allows a port mode that allows a port to simultaneously exist in more than one VLAN, which breaks the virtualization model I talked about earlier. This port mode is found on low-end devices like the Linksys switch he's using; it is typically not found on larger, enterprise-grade switches. You simply cannot set up a Catalyst 3760 to behave the way this guy has set up this little SRW2008.

Here's the problem with how this guy is abusing VLANs. Instead of making each VLAN its own broadcast domain, he's taken an existing broadcast domain and broken it into three pieces. That, by itself, would be ok, provided he then provided routing between those domains to enable them to communicate (at layer 3 instead of layer 2). But he doesn't do that because the switch he's using doesn't offer layer 3 switching. So what he does instead is he selectively violates the integrity of the segregation between the VLANs. This works only because this switch permits the "general" port access mode, which allows multiple VLANs to present on the same port untagged. I've never seen an enterprise switch, at least not from a major vendor, that allows this, and it's generally not a good idea, precisely because it enables a violation of the cardinal rule that every device connected to the same (V)LAN is in the same broadcast domain. (He admits that the ability to do this is "key to our example". Scary.) The crazy thing that ends up happening with this configuration is that traffic that is sent to a device on one VLAN will be replied to on a different VLAN entirely. While this may not create a problem when you're only using one switch that shares its MAC tables across all VLANs, that won't scale up to multiple switches, and this configuration will cause excess unicast flooding in a multiple switch environment (exactly one of the problems it was supposed to avoid), especially if the switch has independent MAC learning on each VLAN. And it's a very tricky and tedious configuration to set up and maintain, far more complicated than a proper setup using access mode ports and a layer 3 switch.

So please, do not ever configure a network like this. The simple fact is that this sort of configuration only works in a small network—and if you have a small network you almost certainly don't have a need to do this sort of thing anyway! In fact, please don't use the "general" access mode even if your switches support it; any time you do you are violating the integrity of the VLAN broadcast domain, and you'll probably end up with hard-to-diagnose network gremlins somewhere down the line, not to mention a configuration that's simply impossible in most upper-end switches. Just stick to one untagged VLAN per port, please; if you find yourself breaking this rule, you've probably done something wrong in your design.

So, now that you've read my rant about why this is the wrong way to go about it and for the wrong reasons, I should tell you a bit about the right reasons. For that, go here. I'm not going to get into the details of how because that varies a lot between switch types. If you want specific help on a specific problem, go here.

H.R. 607, the Broadband for First Responders Act of 2011

2011-02-27T19:17:00.002-06:00

The following is a letter I've just emailed to my Congressman regarding H.R. 607, the Broadband for First Responders Act of 2011. This has been a matter of some discussion by amateur radio licensees in the United States of late. Paper copy will go off in the mail tomorrow.

Please feel free to adapt for your own purposes.

February 27, 2011

The Honorable Mike Quigley
1124 Longworth HOB
Washington, DC 20515

Dear Representative Quigley:

I am writing you today, as a constituent and an amateur radio operator, in reference to H.R. 607, the Broadband for First Responders Act of 2011. This bill claims to seek to establish a supply of radio spectrum available for a public safety broadband network, a goal I have no objection with in principle. However, I wish to bring your attention to a problem with this bill. As introduced, the bill would, if adopted, compromise national security, potentially breach an international treaty to which the United States is a party, and significantly harm the interest of amateur radio operators, all for a purpose that does not clearly serve the stated purposes of the bill. Given that the bill's primary purpose can still be largely met without these negative affects by a relatively simple amendment, I urge you to oppose this bill until the necessary changes are made.

Specifically, I draw your attention to Section 207 in the bill's text. This section seeks to mandate that all current public safety service radio operations currently between 170 and 512 megahertz be moved to the 700 megahertz band. This is mandated not so much to improve public service communications or for any of the other stated purposes of the bill, but instead for two specific purposes: to free radio spectrum to be subsequently auctioned off to wireless communications providers for commercial broadband services, and to force public service entities to purchase new radio equipment. Neither of these purposes directly serves the broader purposes of the bill. Notwithstanding this objection, there is a fatal flaw in this section, relating to the references to the frequency range of 420-440 megahertz. As a brief glance at the Table of Frequency Allocations (47 CFR § 2.106) will reveal, the 420-440 megahertz frequency range is, quite simply, not presently allocated to the public safety service, and so there are no public safety service users to remove from this band.

The 420-440 megahertz band is currently allocated to two separate purposes in the United States. The primary user is the United States government, which uses it primarily for a variety of radiolocation purposes (that is, radar) intended for national defense and border control. The PAVE PAWS early warning radar system, which monitors our coastlines for submarine-launched ballistic missiles and other airborne threats, makes use these frequencies. In addition, the Border Patrol and other federal law enforcement agencies use radar systems on these frequencies to monitor for persons attempting illegal entry into the United States in border areas such as Texas, New Mexico, Arizona, California, and Florida. The secondary user of this band are amateur radio operators, who use it for a variety of purposes with the clear understanding that the military has primacy in the band. Reassigning the band to commercial purposes would almost certainly result in interference with national security objectives.

In addition, within the 420-440 megahertz band there is a subband at 432-438 megahertz that is allocated to amateur radio as a result of treaty obligations that the United States has agreed to by virtue of being a member of the ITU. Part of this band is used by amateurs specifically to communicate with orbiting amateur radio satellites. Those satellites cannot (for fairly obvious reasons) be retuned to different frequencies. While the United States' obligations as a member of the ITU allow the United States to use, or allow the use of, these frequencies for other purposes, allocating them to broadband services (as this bill proposes) would be likely to create a breach of the convention, as those uses would likely cause harmful interference to amateur service operations in other countries as well as to operations in the Earth exploration satellite service (the other internationally-protected user of the band).

It is fairly obvious that the author of this bill labored under the misapprehension that 420-440 megahertz was a public service band, when the reality of the matter is that this band is a radiolocation and amateur service band. Given that the bill was drafted on a mistaken understanding of the current use of spectrum, the only proper thing to do is to correct the bill so as not to refer to this band. I would urge you to refuse to support this bill unless it is amended so as to either remove the references to the 420-440 megahertz band in section 207, or to remove entirely the spectrum reassignment mandated by Section 207.

I urge you to confer with representatives of the Federal Communications Commission and the National Telecommunications and Information Adminstration, with representatives of the divisions within the Department of Defense and Department of Homeland Security that make use of the spectrum at issue, and with the American Radio Relay League (ARRL) in deciding how to proceed with respect to this bill. I also suggest you speak with public safety officials in and outside of Illinois to find out how they feel about being mandated to once again purchase new radio equipment, but that is independent of the issue regarding the 420-440 megahertz band. I am confident that you will determine that reassigning the 420-440 megahertz band away from its current allocation as a military radiolocation and amateur band is not in the best interests of the United States.

If you have any questions regarding my objection to this legislation, please feel free to contact me.

Sincerely yours,

Kelly Martin
(address and telephone number redacted)

Technology is good for ham radio!

2011-02-15T18:46:00.001-06:00

This post is a direct reply to G4ILO's neo-luddite post on his blog entitled "Is technology good for ham radio?" In it, he makes the startling comment, "The more high-tech ham radio becomes, the less magic there is."

Let me put it in short, simple words: there is no magic in ham radio. Ham radio is nothing but technology. Without technology, ham radio is nothing.

Yes, Julian makes a legitimate point regarding the possibility of amateur radio turning into poor copies of existing networks, and I agree with him on the lack of merit of D*STAR specifically. However, there is just as much "magic" in getting a network that combines computer and radio technologies up and running as there is in sending CW with a transmitter made out of parts salvaged from a compact fluorescent lightbulb. Of course we need to keep the ability to do it "simple", because the complicated ways are, fundamentally, built on top of the simple ways. But that doesn't mean we have to stop at simple, and in fact if we do we shoot ourselves in the foot. (It should be noted that Julian states that he uses PSK31 and other digital modes, all of which are less than ten years old or so, so even he doesn't practice what he preaches.)

It never fails to amuse and amaze me how luddite some hams are. I just don't understand how someone who, thirty or forty or fifty years ago, was using a totally newfangled technology to do something can, now, today, be totally unwilling to even entertain the notion that there might be some merit to the newfangled way of doing things.

Ophiuchus, the 13th Astrological Sign?

2011-01-13T16:21:00.005-06:00

I heard today about some noise that's going around about how astrologers have added a new sign to the zodiac, and how this changes everything or some such nonsense. It's sadly fascinating to see stuff like this, because it really exposes the degree to which the Internet has not only not made people less ignorant, but in fact increased the rate at which ignorance spreads. Apparently even Time Magazine is in on this nonsense, based apparently on a press release from the Minnesota Planetarium Society.

Here's the real story.

The ancient Babylonians divided the year into 12 segments, the Babylonians being fond of the number 12 (and also the number 60), and gave names to star groupings that corresponded to each of those twelve segments, enabling them to observe the sky and determine where in the year one was, a very useful skill in a place where the timing of planting is important. The zodiac has exactly twelve equal divisions because that's how it was constructed. It's a human construct, with no natural meaning whatsoever; basically a bookkeeping device. The leading edge of Aries, the first sign of the zodiac, arbitrarily corresponds to the position that the sun is in in the sky on the vernal equinox, the first day of Spring, which is anciently the first day of the year. The key point is that a "sign of the zodiac" is one of twelve equal divisions of the solar year. (These are not to be confused with months, which are anciently defined by the moon's cycle.)

There are, of course, other asterisms in the sky, such as the Great Bear (Ursa Major) and Orion, which are well known to most people but which are not part of the zodiac because they are not in or near to the plane of the ecliptic, the path the sun takes on its apparent annual cycle through the sky. Now let's fast forward to 1922, when the International Astronomical Union (IAU) formally adopted its constellation map, dividing the celestial sphere into 88 named chunks of astronomical real estate. In so doing, they largely kept the traditional Western names for these asterisms (although some of the Southern hemisphere constellations have modern names because those asterisms were not visible to the Babylonians and so they never named them), but the boundaries they settled on did not take into consideration the Babylonian origins of the signs of the zodiac or their astrological significance. As a result of their lack of concern, the ecliptic ended up passing through not twelve constellations (as it would had they remained faithful to their Babylonian predecessors) but indeed thirteen, and the division is not even remotely equal. The thirteenth is Ophiuchus, the Serpentbearer; the ecliptic passes through one corner of the constellation's defined area, although not particularly close to any major star in the constellation. The key point here is that a constellation is one of 88 (unequal) divisions of the celestial sphere.

The thing is, this isn't new. Astrologers and astronomers alike have known about Ophiuchus' intrusion on the zodiac since, presumably, 1922. Some astrologers think this matters; others don't. I've seen complete astrological systems based on the Ophiuchus being part of the zodiac, and I've seen so-called "sidereal" astrologies that take into account precession, which I talk about below. The ones that don't are called "tropical", for some reason I don't recall anymore. Diehard skeptics, of the sort who have a compulsive need to prove astrology wrong, often trot the Ophiuchuan issue forward as "proof" of the wrongness of astrology, along with the precession issue, and it's quite likely that the press release that started all this was motivated by that attitude. Astrology, like all forms of divination, involves the use of essentially randomly-generated symbols to spur self-reflection. The symbols used and their correlations are basically arbitrary; as a result, whether the symbols correspond to anything "real" or not is completely irrelevant. You'll get essentially the same results from astrology using the classical Babylonian/Greco-roman zodiac as you will with using this not-really-new 13-sign approach. Or you can play with Vedic astrology from India if you want something completely different, although the cultural context there may be too foreign for most Westerners to get much from it. Or not. Whatever floats your boat.

In addition, there's an additional complication. The Sun's position on the first day of spring, which originally defined the leading edge of Aries, as I mentioned above, is no longer in Aries. The axis of the Earth's rotation precesses in a cycle of about 26,000 years, causing the apparent position of the Sun against the celestial background to make a full cycle around the sky over that 26,000 year cycle. We're a couple thousand years into the cycle that was started when the leading edge of Aries was defined as the vernal equinox, and as a result the Sun is actually in Pisces on the first day of Spring. In about five hundred years, it'll be in the constellation of Aquarius on the first day of Spring, and according to most astrologers it's already in the sidereal sign of Aquarius, which is the origin of the popular phrase "Age of Aquarius". However, the astrological sign of Aries always starts on the first day of Spring, because that's how it's defined; where the Sun is against the stars in the sky simply isn't part of that definition. The Babylonians almost certainly didn't know about precession of the equinoxes.

Fundamentally the error here is with the Minnesota Planetarium Society, who has unnecessarily (and likely willfully) conflated the astronomical concept of "constellation" with the astrological concept of "sign". A constellation is not a sign, even though there is a historical relationship between two, and in fact twelve of the constellations have the same names as the twelve signs. The IAU did not, in 1922, create a thirteenth sign of the zodiac when it decided to define Ophiuchus to include a bit of the ecliptic. Unless, of course, you decide that you want that to be the case, in which case they did—but only for you.

So if you're a fan of traditional astrology, you can go on using it the way you always have, without worrying about this. It doesn't matter. On the other hand, if you want to worry about it, you can do that too. Just don't lose any sleep over it; that would be foolish indeed. As I mentioned, astrology is an entirely human creation, as are the astronomical names for the asterisms, and these definitions and symbolisms can be changed by humans whenever they want, but only if they want to, and not just because some "skeptic" demands it of them.

Addendum: Apparently AOL's article on this nonsense suggests that the Babylonians deliberately skipped Ophiuchus because "they wanted there to be 12 signs". This claim ignores reality, which is part of the basis of my rant on the Internet being used to spread ignorance. Ophiuchus is certainly near the ecliptic (and there is evidence that Greek and Roman astrologers even read some significance into this, treating the sun's near-passage to a bright star in the asterism as a meaningful event), but the fact remains that the zodiac is defined to have twelve signs in it. The modern fictitious "discovery" of a "thirteenth sign" is merely a consequence of the modern definition of the constellations and has nothing to do with the Babylonians.

The Alphabet, According to Google

2010-12-08T21:49:00.001-06:00

I did this back in September, when "instant search" became available on Google. Basically I typed each letter in and noted the first result.

A is for "Amazon"
B is for "Best Buy"
C is for "Craigslist"
D is for "Dictonary"
E is for "Ebay"
F is for "Facebook"
G is for "Gmail"
H is for "Hotmail"
I is for "Ikea"
J is for "Jewel"
K is for "Kohls"
L is for "Lowes"
M is for "Mapquest"
N is for "Netflix"
O is for "Orbitz"
P is for "Pandora"
Q is for "Quotes"
R is for "Ravinia"
S is for "Sears"
T is for "Target"
U is for "UPS"
V is for "Verizon"
W is for "Weather"
X is for "XBox"
Y is for "Yahoo"
Z is for "Zappos"

Nicki Minaj, Food Network, Turkey and Black Friday: hot topics for November 26, 2010

2010-11-26T13:36:00.000-06:00

I took Thanksgiving off from the blog, it being Thanksgiving, and there wasn't a lot of movement on the hot list since my last post on Tuesday; just the same topics jockeying about. However, today there's several new ones, most of them variations on "Black Friday". Black Friday is, of course, the colloquialism for the first day after Thanksgiving, traditionally considered the first day of the Christmas shopping season, although these days that starts around the middle of October now. Black Friday first started showing up back on November 4th, but the term has been increasingly prominent and appearing in more variations over the past week or so. Best Buy, the electronics retailer, is the first name to pop up; not surprising as their portfolio likely matches best with the interests of internetoholics.

Turkey and the Food Network no doubt both pop up because of Thanksgiving itself and its tradition of gorging ourselves on turkey and other such foods. Although it's now after the fact, I recommend brining your turkey; Alton Brown has a good recipe.

The odd one out (that is, a topic not apparently related to Thanksgiving) is Nicki Minaj, apparently a pink-haired rapper from either Jamaica or Queens. (The pink hair is apparently a wig.) The only interesting thing about her that she seems to be claiming to be bisexual in order to get media attention (or appear sexier) then subsequently denying that she's bisexual to avoid controversy. Most of her gossip-rag media attention (other than the present week, which appears related to an album release) seems centered on speculation about her orientation. The consensus appears to be that she's a "fauxmosexual": fundamentally straight, but willing to act otherwise because that creates buzz and sells records. Whatever; I've already learned way more about this whole cluster of concepts than I ever cared to.

The TSA: Hot topic for November 22, 2010

2010-11-22T10:39:00.001-06:00

After a weekend of the same old topics jockeying about (the only one new one to show up was Erin Barry, who is just another player in the petty drama that I mentioned on Friday), a completely new term showed up late last night. And for once it's actually a matter of some real significance: the TSA, or Transportation Security Agency. The TSA is in the news lately because of John Tyner's now-famous "Don't touch my junk!" ultimatum, issued in San Diego to TSA agents who decided he needed a "pat-down". His outrage has led to a groundswell of complaints and commentary regarding TSA screening practices and made the TSA the whipping boy of the day.

And to be fair, the TSA deserves it. Current US airport security practices were never really calculated to stop determine terrorists. Their main intention was always to increase the general anxiety of the American public about foreign terrorism, in order to perpetuate the need for such invasive practices. This was done for two reasons: one, to make Americans more complacent about having their privacy, and right to travel freely, shredded, and two, to create revenue for the companies that manufacture and sell security solutions. The actual practices used are designed to be extremely visible; that they're annoying just adds to the effect because it just adds to the visibility and thus keeps public anxiety at a high. That they're almost completely ineffective (either as designed or as implemented) in actually stopping a determined terrorist is, quite simply, irrelevant; that was never their purpose anyway. This is "security theatre", plain and simple: the government is pretending to provide security as a cover for what it's really doing, which is eroding your rights a bit at a time, and hoping you won't notice because you're too scared to care.

There is now an Internet-organized boycott of TSA body scanners scheduled for this Wednesday, which is (because of the Thanksgiving holiday) anticipated to be the busiest travel day of the year. The government has already whined about this, urging people not to participate in the boycott because it would create delays at airports. That is, I imagine, the point.

Oh, and for those of you who think you'll just travel by train: Amtrak passengers are subject to security screenings too. For now these aren't as intrusive as those mandated by the TSA at airports, but that could change at any time. TSA has authority over Amtrak and can, at any time, change the regulations for riding on the nation's passenger trains, as well.

Tony Parker: Hot topic for November 19, 2010

2010-11-19T17:37:00.001-06:00

Today's only new item is Tony Parker, a basketball player who is in the spotlight apparently because he was caught sending sexually explicit text messages ("sexting") to the wife of another player (whose name is apparently Erin Barry). This seems to have come out in the context of his divorce, which is, of course, totally unsurprising.

I'm sure this sort of thing goes on all the time, and this is only making the news now because it involves both a basketball player (Parker) of some repute and also a television celebrity: his soon-to-be ex-wife is Eva Longoria, who is apparently somehow involved in Desparate Housewives, which I understand is a TV show of some fame. Ok, whatever: two people who are famous for things I don't generally pay attention to.

Oh well, I suppose the masses need their opiates.

Kate Middleton, Emma Watson and Four Loko: Hot topics for November 18, 2010

2010-11-18T11:24:00.001-06:00

Three new items today, this time from an upcoming movie (Emma Watson), an upcoming royal wedding (Kate Middleton), and an energy drink (Four Loko).

Emma Watson presumably shows up because of her appearance as Hermione Granger in the upcoming Harry Potter movie. I haven't been able to bring myself to read the HP books: first, I am still peeved at Rowling for going after fan websites for "copyright infringement", but more importantly, from what I have read in excerpt and in summary, I just don't like her sort of writing. She breaks at least some of Lawrence Watt-Evans' laws of fantasy; at the very least the second, fifth, and sixth. As far as I can tell, in her books magic is used almost entirely as a macguffin to advance the plot or to create a desired effect, rather than being an integral and necessary part of the fabric of the universe against which the characters interact. (Contrast the role of magic in LWE's Ethshar books, which I adore, or in his equally excellent Dragon trilogy.) I also don't like the racist and classist overtones in her writing. Also, like so many fantasy novelists, I have caught the glimmer of what I call "superman disease": as a series like this progresses the main characters become increasingly powerful, with experience and time, forcing their opponents to be equally inflated so as to make for interesting conflicts. This typically results in each book ending with some massive conflagration, only to be outdone in the next book by an even more massive conflagration. (This does make for good movie material, admittedly.) For another example of this, see Raymond Feist's Riftwar saga, although I think he did well in recovering from that with the later Serpentwar saga, set many years later with entirely new primary characters. Avoiding this basically requires the author to create a complete and consistent universe in which many stories with different characters can be set; this is far harder than just creating a handful of characters and just enough of a universe for them to move around in. Another reason I like Lawrence Watt-Evans.

Kate Middleton is, for those who don't follow the British royalty, Prince William's recently-announced fianceé. Royal-watching is not one of my major pastimes, but apparently both the dress she wore and the ring William gave her are hot items on the "celebrity replicas" market. Ok, whatever.

The last item, Four Loko, is of somewhat more interest: it's one of those caffeinated alcoholic beverages that the FDA has been going after of late. Four Loko is apparently the first such beverage to be decaffeinated in response to the FDA's effective ban on the addition of caffeine to malt liquor beverages. One has to wonder if this will also apply to Cuba Libres or to Irish coffee. Then again I don't think anyone sells a premixed Cuba Libre or Irish coffee (nor would I want to drink such a thing), and besides those are made using distilled spirits instead of malt liquor. Frankly I find energy drinks revolting; while I have no problems with caffeine (I have three or four cups of rather strong coffee a day, and also occasionally drink Mountain Dew or Pepsi when I can find the 'throwback' formulation made with sugar instead of corn syrup), one of either guarana or taurine (I know not which) has a flavor which is nearly vomit-inducing for me. So I'm not going to cry any tears over the loss of these products.

Manny Pacquiao and Skyline: Hot topics for November 16, 2010

2010-11-16T07:47:00.001-06:00

Today brought two new items to the top ten list: Manny Pacquiao (a boxer) and Skyline (a movie).

I'm a bit annoyed to be writing about a boxer or about a boxing match. And so I won't. You want to find out r Frankly I think boxing is just about the most barbaric of the competitive sports we still engage in, even more so than American football, and would be quite happy to see it go away entirely. Boxing was a far higher profile event when I was younger; I think Mike Tyson did a lot to make the sport disrespectable. Which, to be frank, I'm quite entirely happy with. I will admit when I first saw the search term ("Pacquiao v. Margarito") my first thought was "Is a pacquiao some sort of new cocktail?" But that would have been "margarita". My bad.

The other rising item today is Skyline, which is apparently a low-budget alien invasion movie. MTV doesn't seem to think much of Skyline: not good enough to be good, and not bad enough to be good for being bad. I'm almost as uninvolved in movies as I am in sports, so I won't be seeing this one. This is another one where I wasn't able to predict what the search was for; I was kind of hoping it would have been for the chili, but again my hopes were dashed.

Applebee's: Hot topic for November 14, 2010

2010-11-14T10:53:00.001-06:00

There was nothing new yesterday (which is good because I was busy) and only one rising topic today: Applebee's. Best I can tell this is because Applebee's offered free food to veterans on Veteran's Day. Fairly nice of them, even if Applebee's food is some of the most uninteresting food on the planet. I haven't been in an Applebee's in probably ten years; in general I tend to disprefer chain restaurants, favoring instead to eat at unique local establishments.

In other news, I'm working on a ham radio FAQ based mainly on the searches that I see hitting this blog. Not sure how "frequent" these questions are, but anyway.

Keith Olbermann, Cam Newton, and Wiz Khalifa: Hot topics for November 12, 2010

2010-11-12T12:21:00.001-06:00

Once again today, there are four new rising topics today. One of them, Veteran's Day, is out of date (having been yesterday), but didn't show up until today presumably because of the seven day sampling window. Also showing up today for the first time (that I've noticed, at least) are MSNBC political opinion journalist Keith Olbermann, Auburn college football player Cam Newton, and rapper Wiz Khalifa.

Keith Olbermann's appearance in the rising topics comes later than I would have expected (but again, consider the seven day sampling window) after his suspension last Friday (and almost immediate reinstatement) for the offense of donating to Democratic political campaigns. I think the best headline I saw in connection to this was "News flash: Keith Olbermann might be a Democrat!" Anyone who hadn't figured that out by now had to be entirely dense. MSNBC also apparently didn't realize that people would notice that they let Joe Scarborough get away with making donations in previous years. In any case, Olbermann is so transparently partisan that there's no risk that anyone could reasonably suggest that this somehow impacts his "impartiality" as an opinion journalist. Boner move, MSNBC.

Cam Newton is a college football player at Auburn who is apparently the focus of a scandal involving paid recruitment, which is a major no-no in the college football world, even though I suspect nearly every big-name college skirts, evades, circumvents, or just outright ignores the rules in this area. College football is big money, and the big-name colleges (like Auburn) spend a great deal of money on getting the best players so they can get even more money from the businesses who want to use them as walking billboards to drive sheeplike fans to buy merchandise they don't need. College football exploits the players, creates incentives for colleges to make decisions that don't favor academics or the social interests of their students, and has all sorts of disproportionate impacts on women. And with all the recent information on football causing serious, irreversible brain damage, I think it's really time that we reconsider the merits of this "pastime" as a national obsession.

The third rising item today is for yet another bad-boy rapper getting arrested; today's lucky winner is Wiz Khalifa, who was arrested in North Carolina for possession of marijuana on his tour bus. Frankly I don't care if a rapper does pot in his bus, and I don't see why North Carolina should care, either. But if you're a prosecuting attorney, and you can nail a high-profile out-of-state bad boy with an easy bust, hey, go for it. It makes getting reelected easier.

NYC Marathon, Conan O'Brian, Zenyatta, and the Dallas Cowboys: Hot topics for November 11, 2010

2010-11-11T10:56:00.001-06:00

I haven't posted one of these in a few days because there haven't been any new rising terms, just the same ones as previous days, with some permutations in the order. But today were have four new ones.

The Dallas Cowboys are presumably up because they recently fired their coach, but also possibly because they forgot to renew their domain name. Oops.

Conan's up because his new show on TBS premiered on Monday. Conan has became something of a folk hero, especially on the Internet, after NBC gave him the Tonight Show, then ripped it away from him after their ill-considered experiment of putting Leno in prime time predictably backfired.

Zenyatta, meanwhile, is a horse. And apparently not just any horse; this horse had a 19-race unbeaten streak before coming in second by a head in the Breeders' Cup Classic on Saturday. Reportedly she's being sent to pasture to be bred with an "as-yet-undetermined" stallion. I fully expected Zenyatta to be the name of yet another celebrity musician or performer; her being a horse wasn't high on my expectations.

The fastest rising term for today, though, is for the NYC Marathon. It seems odd to me that it should be rising so aggressively now that we're now four days out from the actual event (it was run on Sunday), but the seven day averaging window often means that a single-day spike won't show up for several days. I think marathons are a bit silly (to me running is something you do to get away from bears, not something you do for the sheer sake of it), but to each their own. In any case, I have to admit being rather impressed with Edison Pena, who managed to finish the marathon (in six hours, a firmly respectable time) only a few weeks after being hauled out of a collapsed mine in Chile.

The Kinect: Hot topic for November 8, 2010

2010-11-08T10:22:00.001-06:00

The only new rising topic for today is the Microsoft XBox Kinect (displacing Divali, the Hindu festival of light). The Kinect is, for those who don't already know, an addon for the XBox that provides "controllerless control" by using a combination of posture recognition, facial recognition, and voice recognition to allow control of the XBox merely by moving around within its recognition space. I'm totally not a console gamer at all (the only console game I've ever had was a Pong game my father bought us back in 1978), but I'm seriously impressed by this technology. If it performs half as well as Microsoft claims it does, it'll still be very impressive.

Interestingly, there is already FUD spreading about Kinect: several sources are claiming that the device "doesn't recognize black people", based on a GameSpot comment that the Kinect had difficulty recognizing some darker-skinned employees under certain lighting conditions. In further testing by GameSpot, they were able to make it fail on white people too, and changing shirt colors seemed to make a difference.

It'll be interesting to see how long it'll be before similar input devices become available for use with general computing environments. Probably a while yet. The Kinect isn't that precise, but in the environment it's being used in it doesn't have to be.

Sims 3, Late Night, and Transfiguration of Metals

2010-11-08T00:26:00.002-06:00

Ok, I know, this is a bit off my usual beaten path, but I don't care. I've played the Sims since 2000, and I freely admit to wasting a lot of time on it.

In the Sims 3, since World Adventures, there has been a pair of objects (the Carter XL Display Cases) that can be filled up with objects and "irreversibly transfiguricated" (more commonly known as transfigurated) into other objects. What object one gets as a result of a transfiguration depends on what objects one puts into it, along with some random factors. Various people who know how to look at the scripting language that the Sims uses internally have done so and posted descriptions of the relevant algorithms. I spent quite some time exploring this for the special case of transfigurating metals, and have a simulator now that can predict the result of transfiguration for any particular combination of metals for a game with the World Adventures and Ambitions expansion packs installed (WA+A). I could do the same for just WA if I wanted to set up an install that had just WA loaded, but I've been too lazy to do this yet.

Part of the algorithm for metals works by XORing together the internal OIDs of the metals involved, and then using that as a index into the list of metals (modulo the number of metals) to generate a random metal. The index is then pushed through a PRNG (pseudorandom number generator), and repeated until metals totaling more than a certain value are created. This worked fine and good in prior versions, with the longest string being about 8 or 9 metals in WA+A, where there were 14 metals. However, while in WA alone (which had 13 metals) it was possible (with some care) to create any metal using this process, in WA+A five of the metals (silver, palladium, copper, titanium, and mercury) could not be produced at all, and two more (supernovium and woohooium) were very hard to produce. This is, no doubt, because the low bit of the XOR result is always 0 (because all the OIDs have a low byte of 0), and the modulus 14 of an even number is always even, and so that effectively excluded half of the metals (the ones with odd indices in the metals table) from being the "first result". Add to that a relatively "inaggressive" PRNG and you get a relatively sparse result set, which is what I had noticed with WA+A.

Late Night (LN) added two more metals; as a result, in WA+A+LN, there are 16 metals. Those of you with some experience with generating hash codes will immediately understand where this all goes belgium, but I'll explain it for the rest of you. A modulus of 16 results in only 4 bits of the source value contributing to the resulting index. And all of the OIDs in use have a 0 in the low byte (for whatever reason). As a result, the random value generated by this process is always 0, which corresponds to iron, the cheapest of the metals. To make matters worse, the PRNG EA uses apparently isn't that "random": it appears to map all values that have a low nibble of 0 to values that also have a low nibble of 0. As a result, every metal after the first is also iron. So, instead of getting a "random" (but predictable with much effort) result of various metals (which makes the process both interesting and potentially useful within the context of game play), the result of every transmogrification in Sims 3 with WA+A+LN is a huge stack of iron bars, which is neither interesting nor valuable within the context of game play; furthermore, the resulting stacks are often so large (in some cases, one hundred or more, although the game doesn't show it) that it corrupts the player's inventory, rendering that game effectively unplayable and forcing a retreat to the last save point. Here's hoping you had one.

This wouldn't have shown up in testing with just the base game plus LN, or with A+LN, because in those games there is no transmogrifier (it's a WA expansion item), nor in testing with just WA+LN because in that game there are 15 metals and with 15 metals the randomness of the distribution will be nearly as good as it was in WA alone (with 13), possibly even better.

I had a lot of fun figuring out the matrix for WA+A, and was really looking forward to doing in in WA+A+LN. A shame it had to be completely broken instead. We can only hope that EA will fix this in a forthcoming patch; however, any patch is going to mean a new algorithm (or at least a different PRNG), which means all the work I (and others) did for the preceding algorithm will probably be wasted.

Kik, Diwali, and Lil Wayne: Hot topics for November 7, 2010

2010-11-07T11:13:00.001-06:00

There are three new rising items today: something called "Kik", Diwali, and Lil Wayne.

Kik appears to be the Kik Instant Messenger, which is a substitute IM service for smartphones, available for Blackberries, Android, and the iPhone. The appeal is, supposedly, that you can send instant messages without paying for them, by using your data connection instead of a carrier SMS. The downside is that your recipient has to be using Kik as well. I don't see what this offers ahead of Google Talk, which has been available for all three platforms for far longer, and has a far larger user base as well. Perhaps I'm missing something here.

Diwali is, of course, the annual Hindu festival of lights, which started Friday, November 5th.

The third rising item for today is more celebrity gossip, as rapper Lil Wayne seems to be flaunting his probation by posing for a photograph with a glass of cognac. Not quite sure what it is about rappers that forces them to flagrantly and stupidly break the law, but there you have it.

Daylight saving time ended this morning, so don't forget to adjust any old-fashioned clocks you have that don't automatically adjust. And it's still not too late to change the batteries in your smoke detectors.

Tony Parker: Hot topic for November 19, 2010

2010-11-06T14:42:00.001-05:00

Today's only new item is Tony Parker, a basketball player who is in the spotlight apparently because he was caught sending sexually explicit text messages ("sexting") to the wife of another player (someone by the name of Erin Barry, apparently). This seems to have come out in the context of his divorce, which is, of course, totally unsurprising.

I'm sure this sort of thing goes on all the time, and this is only making the news now because it involves both a basketball player (Parker) of some repute and also a television celebrity: his soon-to-be ex-wife is Eva Longoria, who is apparently somehow involved in Desparate Housewives, which I understand is a TV show of some fame. Ok, whatever: two people who are famous for things I don't generally pay attention to.

Oh well, I suppose the masses need their opiates.

Andy Irons, Demi Lovato, and legal pot: Hot topics for November 5, 2010

2010-11-05T08:34:00.001-05:00

The big item for today appears to be Andy Irons, a pro surfer who died of unknown causes, but possibly dengue fever, on November 2. Dengue fever, now that's a disease you don't hear about much, although it's actually relatively common in less-developed parts of the world. I suppose it's not entirely unreasonable that a surfer might catch it.

The other up-and-coming item has to do with a Disney exploitee by the name of Demi Lovato, who apparently beat up another performer recently. If there's anything that I pay less attention to than celebrity gossip, it's celebrity gossip involving those insipidly disgusting child "performers" being exploited by America's most odious cultural hegemon. Perhaps we could arrange for them to all catch dengue fever. Or, better yet, for their corporate managers to do so.

Searches for election results are, unsurprisingly, rising, with an apparent special focus on those in California and especially Proposition 19, the California ballot initiative to legalize pot there, which failed, gaining only 44% of the vote. I guess the rest of their supporters were too stoned to figure out how to find the polling place. In any case, even if it the proposition had passed there would still have been the federal prohibition on marijuana to overcome. Still going to be a while before you can toke up anywhere you want.

Football player Randy Moss, who I mentioned yesterday, is holding at number 5; I haven't looked to see if there's anything new about him, as I really don't care. The upcoming change back to standard time this weekend fills out the remainder of the top ten for today. Don't forget to change the batteries in your smoke detector.

Capri Anderson, Randy Moss, and Jon Stewart: Hot topics for November 4, 2010

2010-11-04T12:02:00.001-05:00

Apparently the hot story from the past few days has something to do with actor Charlie Sheen, a porn actress called Capri Anderson, and a trashed hotel room. I can't be bothered to make sense out of the social gossip reporting, so if you really care Google's over that way.

Normally I care about as much about sports as I do about celebrity gossip (which is why I am mainly happy that the World Series is over, and so I won't be hearing much about it even if it is still trending up at the moment). However, I must admit that I am slightly amused by the situation surrounding Randy Moss' low opinion of Tinucci's Restaurant, which apparently provides catering services to the team Moss used to play for before recently being traded. In response to his verbal tirade about the quality of their food, the restaurant is offering a free lunch to the first 50 people who show up and agree to trade in their Randy Moss fanwear. Still, I'd be far more interested in Maurice Moss than in Randy Moss any day.

Please note that daylight stupidity time (sorry, daylight savings time) ends this weekend. Of course, having grown up in Indiana daylight savings time seems strange to me. Plus, with the recent changes we're now on daylight saving time from early March until early October, or about two thirds of the year. Frankly I don't see why we don't just leap forward next March and not bother leaping back ever again. It's not like solar noon is anywhere near clock noon in most of the country anyway. But then again, if we did this, how would we remember to check the batteries in our smoke detectors?

Jon Stewart continues to trend high, probably because of the combination of his recent interview with Barack Obama and the Rally to Restore Freedom (and/or Fear) that Comedy Central recently held in Washington. Stewart has, perhaps improbably, emerged as one of the most prominent voices of this generation. I haven't watched any of this week's shows yet—they're on the TiVo—so it's also quite likely that he's had some interesting, or at least amusing, comments on the election results as well.

Limewire continues to trend up even as it disintegrates under the force of the court's adverse ruling in its battle against the RIAA. Hard to imagine what is left for them. This was pretty much inevitable; what surprises me is how long it took and how long Limewire held out.

Searches for "Black Friday", the traditional name for the Friday-after-Thanksgiving shopaganza, are starting to trend up, presumably as people start to plan for their annual shopping fix. There's even an "official" Black Friday 2010 website. Just the other day I heard a radio commentator (WBBM in Chicago) suggest that Black Friday is starting early this year, with pre-Christmas sales starting even before Halloween.

The tenth rising search at the moment is for "Black Ops", which seems strange at first until one realizes it's for the next installment of the Call of Duty franchise, due out in about a week. I don't personally care for first-person (or third-person) shooters, so I won't comment further.

The IT-Who?

2010-08-28T11:48:00.002-05:00

T1B01: What is the ITU?
An agency of the United States Department of Telecommunications Management
A United Nations agency for information and communication technology issues
An independent frequency coordination agency
A department of the FCC
The correct answer is B–A United Nations agency for information and communication technology issues.
(Authority: 97.3(a)(28))

I touched on this topic back when talking about T1A02. The International Telecommunications Union, or ITU, is a very important entity in the broader scheme of radio regulation. The ITU is an agency of the United Nations that deals with information and communication technology; prior to being adopted into the United Nations it was a treaty organization that dealt primarily with the cooperative regulation of telegraphy and other uses of radio across international borders. As radio signals
have a bad habit of refusing to stop at national boundaries, this is
pretty much necessary, especially with respect to the world-reaching HF
bands, in which a station in South America can easily interfere with a
station in Russia. The ITU's rules do not apply directly to amateurs, or indeed to anyone; rather, the ITU makes recommendations which member nations are encouraged to adopt.

The ITU has a significant influence over amateur radio; in their role of creating the International Table of Allocations, they set aside the spectrum that virtually all countries will reserve for amateur radio operators. An example of how the ITU influences amateur radio arose at the World Administrative Radio Conference (a quadrennial meeting of the ITU) in 1979 that resulted in the so-called "WARC" bands of 30 meters, 17 meters, and 12 meters being opened up to amateur use. The United States has historically been one of the most aggressive protectors of amateur radio at the ITU; few nations have as solid a history of arguing in favor of protecting amateur radio spectrum at the international level.

Special operations: Auxiliary stations

2010-08-27T14:37:00.001-05:00

T1A11: Which of the following stations transmits signals over the air from a remote receive site to a repeater for retransmission?
Beacon station
Relay station
Auxiliary station
Message forwarding station
The correct answer is C–Auxiliary station.
(Authority: 97.3(a)(7))

This question broaches, albeit only lightly, the topic of what are called "special operations". There are, in subpart C of the amateur radio regulations, a number of special ways to use, or operate, a radio station that are subject to special rules. These special rules typically impose certain restrictions while relaxing others. For example, an auxiliary station (the topic of this question) is an amateur station (other than a packet station) that is transmitting communications point-to-point within a system of cooperating amateur stations. Auxiliary stations are not permitted to operate on bands below 222 MHz, but are allowed to be automatically controlled (that is, no control operator at the control point). Auxiliary stations which have been coordinated also gain some extra protection against interference, and the general rule against one-way communications is relaxed for auxiliary stations.

The most common use for auxiliary stations is in conjunction with a repeater station. Two linked repeaters may use a pair of auxiliary stations to establish the link, or a remote receiver may use an auxiliary station to connect back to the main transmitter. The W9DUP repeater, operated by the DuPage Amateur Radio Club (of which I am a member) uses an auxiliary station to connect its IRLP node to the repeater, since the IRLP computer cannot be placed at the repeater's location (no Internet access there).

There are several special operations listed in Subpart C, but this is the only one that the NCVEC Question Pool Committee saw fit to include on the Technician pool.

Just what is a "radio station"?

2010-08-18T13:37:00.001-05:00

T1A10: What is the FCC Part 97 definition of an amateur station?
A station in an Amateur Radio Service consisting of the apparatus necessary for carrying on radio communications
A building where Amateur Radio receivers, transmitters, and RF power amplifiers are installed
Any radio station operated by a non-professional
Any radio station for hobby use
The correct answer is A–A station in an Amateur Radio Service consisting of the apparatus necessary for carrying on radio communications.
(Authority: 97.3(a)(5))

More regulatory jargon here. The correct answer above probably seems a bit circular, in that it essentially says that an amateur station is defined as a station in the amateur radio service. But that's about right. A radio station, generally, is simply any collection of devices that, when used together by a sufficiently trained operator make possible communication via radio. What makes a radio station an "amateur" station, and not some other sort of radio station, is simply the intent of its owner for the station to be used in the amateur radio service, as opposed to some other service.

Not necessarily every radio owned by an amateur radio operator, or installed at the location of an amateur radio station, will necessarily be part of that amateur's station. For example, my Android phone contains five radios, and yet it is not part of either of my amateur radio stations since currently my Android isn't directly used for radio communication within the amateur service. (Not that it can't be. There are ways I could use my Android in conjunction with other devices to form an amateur radio station. I just haven't yet.)

Also, despite the term, stations need not be stationary. The use of "station" is something of an archaism from the days when radio transmitters were huge and effectively immobile. Modern transmitters can be quite tiny and thus very portable. Amateurs may also have as many stations as they want. Originally we had to declare to the FCC the location of our "primary" station (and hams in many countries still have to do this) and were allowed only one such "primary" station, but the FCC has long since done away with this. US hams may have as many primary fixed stations as they want (including none), and may have as many additional portable and mobile stations as they can afford. The FCC used to require that certain classes of station (auxiliary, repeater, and beacon stations) be separately licensed, but that requirement has also been done away with and any ham (other than a Novice) may operate any number of stations in one of these special operational modes with no special notice to the FCC.

Frequency coordination

2010-08-17T15:31:00.001-05:00

T1A08: Which of the following entities recommends transmit/receive channels and other parameters for auxiliary and repeater stations?
Frequency Spectrum Manager
Frequency Coordinator
FCC Regional Field Office
International Telecommunications Union
The correct answer is B–Frequency Coordinator.
(Authority: 97.3(a)(22))

T1A09: Who selects a Frequency Coordinator?
The FCC Office of Spectrum Management and Coordination Policy
The local chapter of the Office of National Council of Independent Frequency Coordinators
Amateur operators in a local or regional area whose stations are eligible to be auxiliary or repeater stations
FCC Regional Field Office
The correct answer is C–Amateur operators in a local or regional area whose stations are eligible to be auxiliary or repeater stations.
(Authority: 97.3(a)(22))

These questions only briefly touch on an issue in part because going deeper into it would touch on areas on which the amateur radio community is in disagreement. The prior version of the Technician pool had two questions on this issue, and one of the questions set forth the arguably controversial position that coordination "reduce[d] interference and promote[d] proper use of spectrum". I don't know why the NCVEC dumped those two questions in favor of these, but at least these questions are much more closely tied to the actual definitions in the regulations.

Frequency coordination, in general, is the recommendation of operating frequencies (transmit and receive parameters) and other parameters (such as antenna gain, antenna directionality, and selective squelch) to allow multiple repeater and auxiliary stations operating in the same general area to interoperate with a minimum of interference. In the business services frequency coordination by an FCC-recognized frequency coordinator is mandatory for all applicants, and applicants must generally pay a fee to the coordinator for that service. In the amateur service, coordination is strictly optional; however, the regulations give an advantage to repeater and auxiliary stations that do coordinate by essentially giving them priority over uncoordinated stations in an interference dispute, but only when the other interfering station is also a repeater or auxiliary station.

In principle coordination, when properly done, should reduce interference and encourage better utilization of spectrum. Unfortunately, it rarely works out that way. Frequency coordinators have a tendency to become "old boy" clubs that seek to protect the interests of their friends at the expense of those who are not their friends. My personal recommendation with respect to coordination is that one should avail oneself of the service if and when it is offered under reasonable terms, but not let it get in the way of doing something interesting or useful, especially if the coordination body is nonresponsive or unreasonably obstructive.

The other interesting thing about coordinators is that there's no top-down process for selecting one. Instead, the amateur radio operators (at least those eligible to be repeater or auxiliary station operators, which is everyone except Novices, and the FCC has proposed allowing Novices to be repeater operators, too) in an area choose, by no defined process, who their coordinator is. What this means, as far as I can tell, is if enough hams in an area get together and coordinate frequencies amongst themselves, and are recognized as having done so, then they've formed a coordination body and are acting as a "frequency coordinator". The FCC's regulation is very silent on what happens if there's a disagreement over who has jurisdiction in a particular area or if there are two competing entities both claiming to be "the" frequency coordinator for a given area. The key here is that the recognition process is bottom-up rather than top-down.

Finally, don't confuse frequency coordination with the bands established by the FCC (and consistent with ITU policy directives). FCC-set band allocations establish the limits of the frequencies on which an amateur may operate, with specific power limits and modulations. Also do not confuse frequency coordination with the voluntary band plans recommended by the ARRL (and other entities) for general use of frequencies within the limits of the FCC allocations. Frequency coordination is always a specific recommendation for a specific repeater or auxiliary station, based on the particular characteristics and expected usage of that station.

(Edited 8/18 to add T1A09.)

Remote control and intelligence: telecommand and telemetry

2010-08-17T11:08:00.003-05:00

T1A06: What is the FCC Part 97 definition of telecommand?
An instruction bulletin issued by the FCC
A one-way radio transmission of measurements at a distance from the measuring instrument
A one-way transmission to initiate, modify or terminate functions of a device at a distance
An instruction from a VEC
The correct answer is C–A one-way transmission to initiate, modify or terminate functions of a device at a distance.
(Authority: 97.3(a)(43))

T1A07: What is the FCC Part 97 definition of telemetry?
An information bulletin issued by the FCC
A one-way transmission to initiate, modify or terminate functions of a device at a distance
A one-way transmission of measurements at a distance from the measuring instrument
An information bulletin from a VEC
The correct answer is C–A one-way transmission of measurements at a distance from the measuring instrument.
(Authority: 97.3(a)(45))

Many of the questions in the first section of the licensing exams are about regulatory jargon, and these two are no exception. I've combined these two into one post because they're basically opposite sides of the same coin. Both are examples of one-way transmissions. Also, notice that the correct answer to each question is a distractor on the other one; it is therefore important to read the question closely to see which one you got.

Telecommand is what your TV remote does: it sends commands to your TV, causing your TV to "initiate, modify, or terminate functions" based on what button you pushed. Of course, your TV remote is probably infrared (very few television remotes are RF these days), but the principle is the same. Perhaps a better example that almost always uses RF is a garage door opener.

Telemetry is using wireless communication to receive data from a measuring device without a physical connection between the measuring device and the reporting or recording device. If you have a wireless weather station, what that uses to send the gathered data back to the base station is telemetry. The same would apply to a wireless security camera; in this case the data being reported back are the images being captured by the camera.

In the context of amateur radio, telecommand is the use of amateur radio frequencies to remotely control a device. This device can be anything at all, but two specific categories stand out: remote control of model craft (often model airplanes), and remote control of space stations; these two categories receive special treatment within the rules. But nearly anything, even another amateur radio station, may be controlled by telecommand.

One of the most common telemetry activities in amateur radio today are APRS telemetry stations (often called "beacons", which is technically a misnomer, as they're not really beacons, but instead telemetry stations). APRS telemetry stations periodically transmit their location (and possibly other data, such as weather observations, environmental conditions, or anything else the station operator feels like reporting) via a packet data format which may then be received by an APRS digipeater and eventually captured by an APRS gateway and published on the Internet.

Space stations: it's all about altitude

2010-08-17T10:25:00.002-05:00

T1A05: What is the FCC Part 97 definition of a space station?
Any multi-stage satellite
An Earth satellite that carries one of more amateur operators
An amateur station located less than 25 km above the Earth's surface
An amateur station located more than 50 km above the Earth's surface
The correct answer is D–An amateur station located more than 50 km above the Earth's surface.
(Authority: 97.3(a)(40))

Yet another question about radio regulatory jargon. The term "station" is, itself, specialized jargon in the radio services; despite the name, a "radio station" does not have to be stationary. A "space station" is, within the context of regulated radio (and thus amateur radio), simply a radio station in space. "Space" is defined as "anything more than 50 kilometers above the earth's surface".

The common notion of a space station typically requires that the station be manned; however, this thinking will again throw one off the radio definition. Space stations, in the radio sense, may be remotely operated or automatically controlled, just as any other station, and so a manned presence is not required. Nor is a space station required to be in earth orbit (although as far as I know there are presently no amateur space stations which are not in earth orbit). An especially high-flying balloon would count (although typically amateur radio ballooning activities tend to top out below the roughly 160,000 feet that defines "space"); so would a station on an object in solar orbit (such as, say, Mars) or even on a solar escape trajectory.

Amateur radio space stations have a lot of special rules that apply to them, but unless you plan on launching something into orbit you probably won't need to worry about them. The key to getting this question right on the exams is remembering two things: stations do not have to be manned, and anything over 50 kilometers is "space".

Harmful interference

2010-08-16T11:53:00.001-05:00

T1A04: Which of the following meets the FCC definition of harmful interference?
Radio transmissions that annoy users of a repeater
Unwanted radio transmissions that cause costly harm to radio station apparatus
That which seriously degrades, obstructs, or repeatedly interrupts a radio communication service operating in accordance with the Radio Regulations
Static from lightning storms
The correct answer is C–That which seriously degrades, obstructs, or repeatedly interrupts a radio communication service operating in accordance with the Radio Regulations.
(Authority: 97.3(a)(23))

"Harmful interference" is another term from the jargon of radio regulation. Interference, broadly speaking, is anything that tends to disrupt communication, regardless of source. Not all interference is "harmful", though. Merely being "unwanted" or "annoying" is not enough to rise to the level of "harmful"; the disruption has to be significant or repeated, or must completely prevent all communication, before it rises to the level of harmful. Finally, "harmful interference" never originates from a natural source, so static from lightning storms, no matter how annoying or disruptive, doesn't count as harmful interference.

All radio licensees, including amateurs, are prohibited from causing harmful interference with any other station. Stations who are suffering from harmful interference are entitled to relief from that interference, which means that the station causing the harmful interference can be made to stop, by force if necessary, by the governing administration that has authority over that station.

Harmful interference doesn't have to be intentional, although it often is. Jamming (that is, transmitting on top of other transmissions in order to block them) is an especially pernicious form of harmful interference. But that's not the only form of harmful interference; far more common are things like spurious emissions caused by malfunctions or maladjusted transmitters, leakage from cable television systems, and unwanted noise from defective household electronics like computers or televisions. All of these, if severe enough, count as harmful interference that can result in enforcement actions from the FCC.

In practice the FCC's effort to abate harmful interference is proportional to what the licensee suffering the interference pays in licensing fees for their license; since amateurs pay nothing for their licenses the FCC doesn't work terribly hard to resolve interference complaints. Basically that means we have to investigate the circumstances ourselves and wrap the whole thing up nice and pretty so all they have to do is some quick work to verify the complaint before they'll act. Fortunately the ARRL is actually pretty good at this; one of the few things they do do well.

This particular question is one that was improved in this version of the question pool; in the 2006 question pool the question misstated the definition of "harmful interference", leading me to complain about it when I blogged about it about a year ago.

Part 97 of how many?

2010-08-16T09:52:00.002-05:00

T1A03: Which part of the FCC rules contains the rules and regulations governing the Amateur Radio Service?
Part 73
Part 95
Part 90
Part 97
The correct answer is D–Part 97.

The FCC, as I mentioned in the previous post, regulates all nonfederal use of radio for communication in the United States. In the course of doing this it issues lots and lots of regulations. These are gathered together (along with selected regulations from certain other agencies) in Title 47 of the Code of Federal Regulations. For bureaucratic reasons, the regulations are divided into numbered "parts"; the FCC is allotted parts 0 through 199. The first twenty parts (0-19) are for administrative and general rules that apply to the FCC and its licensees generally. The remaining parts, 20 through 101, are rules for different types of licensed radio uses, or "services", as they are known in radio regulatory jargon.

The four answers the NCVEC offers for this question are therefore all rules for specific radio services. Part 73 contains the rules for the broadcast media services, including AM and FM radio, television, and the international broadcast service (shortwave). Part 90 contains all the rules for what is known as the "private land mobile" service; this rather large division includes business radio and public safety radio (such as police and fire services). Part 95 covers the "personal radio" services such as CB and GMRS. And, finally, Part 97, the correct answer, covers the amateur radio service. It's generally a good idea for hams to have a copy (at least in electronic form) of Part 97 simply because the FCC expects us to be aware of the rules of the service.

The astute reader will already have noticed that when I quote the questions in these posts, there is often an "authority" section at the bottom of the question (although not in this post, because the NCVEC didn't provide an authority for this question). These are references, provided by the NCVEC, to the portion of the FCC regulations that the question under discussion is testing. These references are hotlinked to the Government Printing Office's Electronic Code of Federal Regulations Service, which is updated daily and is therefore the most up-to-date and official source for these documents (even more so than the FCC itself). There are other sources for Part 97 out there, but if you use a source other than the GPO, please ensure that the source you use is up-to-date; the FCC has amended Part 97 twice already this year alone.

What does the FCC have to do with amateur radio?

2010-08-16T07:45:00.001-05:00

T1A02: What agency regulates and enforces the rules for the Amateur Radio Service in the United States?
FEMA
The ITU
The FCC
Homeland Security
The correct answer is C–The FCC.
(Authority: 97.1)

This is another question that's in the question pool to ensure that aspiring licensees are educated about something that is very important to know: that amateur radio, in the United States, at least, is regulated by the Federal Communications Commission, or FCC, and not by any other entity.

The FCC has been charged since its creation in 1934 with the regulation of all uses of radio frequency energy for communication within the terrority of the United States, its coastal waters, and ships at sea sailing under the flag of the United States, except for use by instrumentalities of the federal government itself (over which the FCC has no jurisdiction). Amateur radio falls within this scope, and so amateur radio is regulated by, and the rules for amateur radio written and enforced by, the FCC.

Two of the other three entities listed are other federal agencies that have no authority over radio: FEMA and Homeland Security. Hams have no specific duties, functions, or responsibilities with respect to either FEMA or Homeland Security. The third entity offered as a distractor is the ITU, or International Telecommunication Union. The ITU, unlike the others, is not a federal agency; it is instead an agency of the United Nations, formed originally in 1865 as the International Telegraph Union in 1865 by a multilateral treaty amongst 20 nations. The United States is a charter member of the ITU and, as a member nation, agrees to abide by the regulations the ITU sets forth regarding radio. However, while the FCC will only rarely write regulations that are inconsistent with those issued by the ITU, it remains the case that it's the FCC regulations, and not the ITU regulations, that apply to amateur radio in the United States. Which is just as well, because the FCC regulations anyone can get for free from the US Government Printing Office, while the ITU regulations are not available without the payment of a fee to the ITU, or more accurately the ITU's publisher.

The FCC isn't the only entity that a ham has to care about. Hams must also follow FAA regulations (when erecting towers over a certain height, as set forth in Part 17). Hams must also be aware of and follow certain regulations of the National Technology and Information Agency (NTIA), issued as part of the latter's authority to coordinate the use of radio by the federal government. Several amateur bands are shared with federal users (including the military) and amateurs must be aware of the NTIA's regulation of those shared bands and observe any restrictions placed by NTIA in the use of those bands. Finally, while FCC regulation preempts state and local regulation of radio with respect to radio frequency interference and radio frequency exposure safety, state and local authorities may still enforce "reasonable" regulations on antenna structures for the purpose of electrical and mechanical safety and other "legitimate" purposes.

In practice, the FCC governs with a relatively light hand. Amateur radio is a tiny tiny piece of the FCC's pie. Amateur radio licensing generates very little revenue for the FCC (as the licenses are free), and they put relatively limited resources into the amateur radio area. In general the FCC expects us to take care of ourselves. This is a mixed blessing: on one hand it means that the FCC isn't something we generally have to deal with much; on the other hand, when there is a problem, getting the FCC to act on it can be difficult. It's not clear to me that a heavier hand would be better for amateur radio, though, and the other alternative (no amateur radio at all) is clearly worse.

Who Is Amateur Radio For?

2010-08-16T00:39:00.004-05:00

This is the first post in what is likely to be a long series that discuss the material on the Amateur Radio licensing examinations. Each post will typically focus on one question from the question pools; there are thousands of these questions so this will probably go on for some time. Some of this material will likely be repetitive with prior posts in this blog, but I will try to make it interesting nonetheless.

T1A01: For whom is the Amateur Radio Service intended?
Persons who have messages to broadcast to the public
Persons who need communications for the activities of their immediate family members, relatives and friends
Persons who need two-way communications for personal reasons
Persons who are interested in radio technique solely with a personal aim and without pecuniary interest
The correct answer is D–Persons who are interested in radio technique solely with a personal aim and without pecuniary interest.
(Authority: 97.3(a)(4))

This question's presence in the Technician pool acts to ensure that people who are setting out to become hams will understand both what amateur radio is and also what it is not. Amateur radio is not (as is widely believed, if you believe the random noise I hear on Twitter and Backtype) a means by which one can broadcast one's opinions to myriads of rapt listeners. Nor is it intended as a personal communication service (either with your friends and family, or as a general chat service); people looking to do that should consider whether one of the Personal Radio services, or even a cell phone, would better serve their needs. Amateur radio is intended to allow those who have an interest in radio for its own sake a means to explore and develop their interest. If you are hoping to accomplish something useful, and you're just considering using radio as a means to do that, amateur radio may not be what you're looking for. Especially if the thing you're hoping to accomplish involves making money for yourself or someone else: that's specifically prohibited.

As it happens, the foregoing notwithstanding, there's quite a lot of use of amateur frequencies for what amounts to the broadcasting of opinion (as anyone who has listened to 75 meter phone, or to far too many VHF repeaters, can attest), and it's certainly common to see amateur radio used for personal communication between family members, or for general chatting (the latter is often called "ragchewing"). It's just that these are not part of the principle purposes of the amateur radio service, and the FCC offers other services which are explicitly intended for these purposes.

Fundamentally, if you think the whole concept of flinging signals through the air and catching them halfway across the world (or just halfway down the street) is really awesome and want to play with this more, and are willing to take quite a bit of time to learn some pretty complicated stuff, then ham radio is for you. If you just want to talk to people halfway around the world (or, again, halfway down the street), well, may I suggest Twitter? It's a lot easier to get on Twitter than it is to get a ham radio license, after all, and you don't have to buy nearly as much equipment. Fundamentally, ham radio is a geek thing; if you don't have the knack, then it might well not be for you.

Electrocution may be hazardous to your health

2010-06-04T01:24:00.001-05:00

The first group of new questions from the 2010 Technician pool I'm covering are from subelement T0, which covers safety issues. The NCVEC has been increasing the amount of safety-related content on the tests in recent years, and the new pool contains 13 new questions in this subelement. The first of these is T0A02: "How does current flowing through the body cause a health hazard?" I would think that most people understand that being electrocuted is bad for them, and generally something to be avoided. However, for whatever reason, the NCVEC has decided that it's at least somewhat important for new hams to be prepared to demonstrate that they understand just why electrocution is bad for you.

There are three main ways that electric currents within the body are hazardous. First, any current flowing through any medium which is not a perfect conductor (which is to say, anything whatsoever) generates heat (sometimes called Joule heating). The body's internal resistance is modest, typically between 300 and 1000 ohms; however, the skin resistance can be much higher, in the 10,000 to 100,000 ohm range depending on conditions. A current passing through the body will heat and eventually burn tissue, preferentially at points of higher resistance; this will lead initially to burns on the skin and then later (as the skin blisters and its resistance lowers), to burns deeper within the body. Second, many functions of cells depend on electrical charges, and the moving about of charged ions, to accomplish the purpose of the cells; electrical currents passing through these cells will tend to disrupt these electrical functions. At very low currents (1 milliamp or less) this manifests itself as a tingling sensation. At higher currents it will manifest as pain. Sufficiently high currents (50 to 70 milliamps) may cause the third major effect: involuntary muscle contractions. At even higher currents, 500 milliamps or more, the muscle of the heart can be disrupted leading to heart fibrillation, cardiac arrest, and death.

This particular question appears in the pool with an "All of the above" option. Any experienced test-taker knows that "all of the above" is often the correct answer to any question that has such an option, and this question is no exception to that rule. In any case, what really matters is that hams must understand that electrical voltages, even relatively low ones, are potentially dangerous, and must take precautions to avoid finding out about these effects first-hand.

New Technician Pool, coming soon to a VE team near you

2010-06-03T02:49:00.001-05:00

The NCVEC announced a new Technician pool back in February; it's now June and that new pool goes into effect July 1. I've been blogging about the old Technician pool (an activity which, of late, I have been kinda lax at), and I've decided to abandon that effort in favor of blogging about the new pool, on the grounds that that might be more useful.

The new pool has 396 questions, 5 more than the old one; there are 67 questions carried across unchanged, 142 carried across with some changes (either minor or, in some cases, major), and 187 questions that are entirely new. 182 questions were dropped. I would say that this new pool is somewhat harder than the old one; the new pool has significantly more electronics on it as well as content related to ionospheric propagation and SSB and CW operations (reflecting the fact that all Technicians now get limited HF privileges, not just those few who pass a code test). There's even a few basic antenna theory questions. Overall I think this is a better pool, in that it will force candidates to learn more of what they should know as beginning amateur radio operators.

Future posts will discuss specific topics that are new or newly handled on the new pool.

Don't drive in Northlake this weekend

2010-05-28T11:50:00.004-05:00

I guess Northlake is short on money or something: I just got a $50 "seatbelt violation" (given to me by NLPD Officer Carpenter, badge #128) for driving while wearing a seatbelt. Yes, you heard me. For driving while wearing a seatbelt.

The incident occurred near the intersection of Fullerton and Roy, around 11:15 am today. This is a common place for Northlake to set speed traps, and I know this, so I was being careful to watch my speed through here. I noticed the cop (in his tiny little Northlake compact cop car, they don't drive Crown Vics there) as I drove by, and even nodded to him. I'm driving my GMC Sierra, which means I'm probably 4 feet above his eye level: there is no way he can tell if I'm wearing my seat belt or not. I always wear my seatbelt. Always. No exceptions.

After I clear the intersection he lights up and chases me down a half block down the road. I pull over, of course, and go to get the insurance card out of the glove box while waiting for him to walk up. In order to do this, of course, I have to take off my seat belt: the glovebox on a Sierra is a LONG reach and it's really hard to do without removing the seat belt, so when he gets to me I have already taken my seat belt off. He gets to me and tells me that he pulled me over for not wearing a seat belt. I tell him that that's ridiculous, and he gets all hot and huffy at me (including the classic "You got a problem with that?" line that dumbass powerfreak cops use all the time). He takes a brief look at my license and insurance (probably just to verify that I don't live in Northlake: I don't, and my license still has my Niles address on it) and decides at that point that he's going to write me a citation.

The fine is $50, and I'm not going to fight it because the only way I can win is to hope that Officer Carpenter doesn't show up. Basically this is the Northlake Mafia, tagging me for $50 for being in the wrong place at the wrong time. I actually figure I'm better off having taken my seat belt off before he got up there; otherwise he'd have to come up with some other bogus violation to charge me with that would have cost me more and maybe even put points on my license. But this certainly is a huge discouragement for me to do any business in Northlake, especially this weekend.

Quick note to Mayor Jeffrey Sherwin: antagonizing your neighbors is not a good business practice. I can easily take my business in Northlake to Melrose Park, Stone Park, or Franklin Park.

Station identification

2010-02-04T16:13:00.000-06:00

Anyone who has listened to broadcast radio knows at least a little about station identification requirements; I certainly remember listening to the Indy 500 coverage back in my youth (I grew up in Indianapolis, so we were blacked out for TV coverage and could only listen to the race on the radio) and remember well the periodic interruption of the coverage with "We now pause 15 seconds for station identification" followed by WIBC's identification as the network flagship station. The general rule is that radio stations must, from time to time, transmit identification so that listeners will know who is transmitting. The main regulatory reason for this is so that a station that is suffering harmful interference from another station can, merely by listening long enough, identify who that station is and seek relief appropriately, or determine that they are not entitled to relief. Amateur radio stations are no exception to this general rule, although the specific requirements are different than for the broadcast services.

The general rule for identification in the amateur radio service in the United States (§97.119) is that station identification is required at the end of a transmission or series of transmissions, and at least once every ten minutes during a transmission or series of transmissions which lasts longer than ten minutes. Note that there is no requirement to identify at the start of a series of transmissions, and identification at the start of a series of transmissions is insufficient to meet the requirements of the rule. In general, the best way to remain in compliance with the rules is to ensure that you always end out your transmission with your identification.

In general, transmissions which do not include identification (known as "unidentified communications or signals") are prohibited, with two very specific exceptions. First, stations operating more than 50 kilometers above the earth's surface ("space stations") are not required to identify under any circumstance. Second, stations being used solely to control a model craft (via telecommand) are not required to identify provided that the transmitter being used has a label affixed to it identifying the licensee's call sign, name, and address, and that the transmitter's power does not exceed one watt. Note that while telecommand signals sent to a space station are permitted to be encrypted, such transmissions are not exempt from identification. The only type of transmission which is both exempt from identification and permitted to be encrypted is telecommand of a model craft under §97.218.

The identification itself must be a call sign. In general, it'll be the call sign of the operator, but there are several situations in which it can be a different call sign. In general, when operating someone else's station you are supposed to use their call sign, not your own call sign. When operating a station owned by, or being operated on behalf of, a club, the operator should identify using the club's call sign. Also, a station which is operating within the scope of a "special event" may identify using the temporarily assigned special event call sign in lieu of his or her own call sign. In all of these cases, the operator must have the permission of the station owner, the club's trustee or the special event coordinator (respectively) in order to use the call sign. Furthermore, when using a temporarily-issued special event call sign the operator must identify with his or her own call sign at least once in every hour; however, this is not required when using someone else's permanently-issued station or club call sign.

The rules stipulate that station identifications must be transmitted in one of four formats: Morse code, phone (in English), RTTY, or a video format as specified in §73.682(a) (which is part of the FCC's standards for broadcast video); the latter two options apply only if the transmission being identified was in a digital mode or video mode, respectively. In practice, very few stations transmitting digital modes other than RTTY identify in RTTY, identifying instead in the same mode as the transmission, and the FCC has yet to take action against any station for failing to identify, but that's what the rules require. (The regulations relating to digital modes are rather out of date in places, and actual practice is often rather at odds with the regulations, but nobody seems to care a whole lot.)

There's a lot of common myths in the amateur community relating to identification. A common one that is seen with older VHF ragchewers is the practice of identifying in a roundtable with "K9XYZ and the group, this is W9ZXY", and some hams seem to think that this practice is mandatory. The regulations never mandate transmitting the call sign of any station other than that the station transmitting. It is not necessary (in regulation, at least) to identify the intended recipient of the transmission. This particular practice seems to have arisen from an overly zealous interpretation of the regulations relating to broadcasting; someone decided that all communications had to involve exactly two stations, and that identifying in this manner would somehow satisfy this regulation. The only requirements for two (or more) stations who are communicating with one another is that each station must end its final transmission in the exchange with its own call sign, and each station must identify with its own call sign at least once every ten minutes during the sequence of communications.

There's a few situations in which one is required to add indicators either before or after one's call sign, when identifying. If you're operating someone else's station and you are exceeding the privileges alloted to the licensee of that station, you are required to identify by using the station owner's call sign followed by your own call sign, to explain why that station is entitled to operate in those frequencies or modes. There's also three special suffix indicators (/KT, /AG, and /AE) used to indicate that the station operator has recently upgraded and is using the privileges gained thereby pending the processing of the upgrade by the FCC. These are pretty rare now, though, given the speed with which the FCC processes upgrades these days. Also, when operating in the United States pursuant to a reciprocity grant, the alien operator is required to prefix his or her own (non-US) call sign with a call sign prefix identifying the location of the station. Perversely, for Canadians this goes after, not before, the call sign. (The same rule applies for a US licensee operating in another country, except, of course, in reverse.) Licensees may add additional voluntary designations either before or after their call sign if they so choose, as long as such designations do not conflict with any of the official ones. It's quite common to see "/R" added to repeater station identifications, for example, even though this is (no longer) required by the rules, and many older hams will reflexively add "mobile" to their identification when operating mobile because that used to be required. The requirement of not conflicting with official designations effectively eliminates most voluntary prefix options because nearly every possible code is a valid national prefix and would therefore be in conflict. (Out of 1296 possible two-character codes, 1034 are currently assigned.) However, voluntary suffix options are pretty much wide open.

Speaking of myths regarding identification, the NCVEC perpetuates the myth that the "KT", "AG", and "AE" suffixes are initialisms in question T2B11, which tests whether you know that "AG" supposedly means "Authorized General". The regulations do not specify the use of "Authorized General" when identifying in English when operating pursuant to a CSCE granting General privileges; they specify the specific use of the suffix "AG", which in phone would be "Alpha Golf". The reason "KT" is used for Technicians instead of "AT" (which would make more sense) is because "AT" is not a call sign prefix available to the FCC (it's allocated to India) and the FCC, when it selected those suffixes, wished to avoid conflict with other possible uses. "Authorized General" is essentially a backronym from the fundamentally meaningless code. (T2B11 is another example of a bad question; fortunately, this one, like the other bad question I wrote about a while ago, appears to have been dropped from the 2010 version of the pool.)

This post has been brought to you by pool questions T2A05, T2B01, T2B02, T2B03, T2B04, T2B05, T2B06, T2B07, T2B08, T2B09, T2B10, and T2B11. Section references above are to Title 47 of the Code of Federal Regulations, browsable via the GPO Access eCFR service.

Mars is greener than you might think

2010-02-03T20:37:00.000-06:00

A while back I was watching some TV show, quite likely a documentary of some sort, that talked about the American effort to land a man on the moon in the 1960s, and more specifically how that goal became a major driver in the American economy during the 1960s. That concentration of effort is no doubt a huge part of why America was the global leader in technological innovation up to the turn of the century. The Apollo program wasn't all that expensive. The government spent, over ten years, between $20 and $25 billion in 1969 dollars (around $150 billion in today's dollars) on the Apollo program, and the government recovered all of that within less than a decade due to increased tax revenues related to the subsequent commercial exploitation of the technologies developed by the space program.

It does rather seem that a major space mission is a good economic driver as well as a very potent way to build national pride in a nondestructive way (we get to win without anyone else really losing). The problem is that we've already been to the moon; doing it again isn't very interesting unless we establish a permanent base these. The next obvious targets are Mars and Venus; Venus is closer but the surface is too hot for even a mechanized lander to last long, and a manned mission would have no chance of setting foot on Venusian soil with present materials technologies. So that leaves Mars as the obvious choice for the next place to send a manned mission, and so when this topic comes up (as it did recently in connection with the fortieth anniversary of Apollo 11) that's what is usually proposed.

There are two main difficulties in a mission to Mars: getting there, and getting back. And it's not the astrophysics that are difficult: we know how to do that by now. It's the biosphere management required to keep some number of humans alive (that is provided with air, water, and food) for the entirety of that trip, which will take months. The missions to the moon were short, only a couple of days, and it was practical for the astronauts to take their consumable supplies with them and to jettison their waste as they went. A Mars mission has no such option; if they tried to pack a year's worth of air, food, and water in the ship it would take years just to boost it all into earth orbit for assembly. To have any hope of being launched in a reasonable time, a Mars mission will have to construct a closed biosphere capable of sustaining the crew, with only sunlight as an external input, for the entirety of its mission; they will have to recycle virtually everything on board and very carefully manage their limited resources.

Now, doesn't that sound like it should be right up the Green Party's alley? The need for the technologies required to build a self-sustained closed biosphere capable of supporting a crew of several humans for a year would naturally drive research into all sorts of areas that have immediate and obvious application to waste management and reprocessing, resource recovery, and other aspects of environment management that are just the thing for advancing technologies in ways to pollute our own planet less and place fewer demands on its limited natural resources. I would think that Greens would be the loudest advocates for a manned mission to Mars because of this, yet the word "Mars" does not even appear in their 2004 platform statement, and in fact the Greens appear to oppose manned exploration of space due to the "high cost and risk for human life". I suppose they haven't really thought about this that much.

It seems clear to me that a Mars mission could lead to a technological Renaissance in the life sciences the way that the Apollo missions did in the material sciences and in electronics, with huge benefits to all mankind and especially to whatever nation does it first. But we won't know unless we try.

Odd things you find while looking for work

2010-01-29T12:46:00.001-06:00

Came across a job posting today on sologig for a SharePoint Analyst that had one of the oddest job requirements I've seen yet. Apparently this employer believes that a qualified candidate will be able to "[p]repare strategic business requirements, uses accepted concepts, standards, SDLC methodologies, and toilets".

Now, I would think that applicants for most jobs in the United States would generally be expected to be toilet-trained, and in any case not being toilet-trained would probably fall within the scope of a protected disability under the ADA. Maybe one of the duties includes maintaining the programmer's restroom.

Original listing here; saved for posterity here for when the posting expires or is "corrected".

More things you can't do on amateur radio

2010-01-18T04:30:00.000-06:00

I wrote a while back about some of the things you cannot do on amateur radio. Here's some more of them.

First of all, amateurs are forbidden from broadcasting: that is, amateurs are prohibited from making transmissions of content transmitted with the intention that it be heard by the general public, either directly or indirectly. That doesn't mean that hams aren't allowed to make one-way transmissions, it just means that an amateur may not use his or her amateur station, in general, to talk to people who aren't also amateurs. It's important to understand that certain one-way transmissions such as a CQ call, QST bulletin, or telemetry transmission are not "broadcasts" because they are not intended to be heard by the general public, but instead by "all amateurs" or "amateurs with an interest in this communication". The key to the definition of "broadcasting", which is entirely prohibited to the amateur service, is that the communications must be intended to be received by the general public. Obviously this regulation is to prevent amateur stations (with their zero license fee) from competing with the broadcast service. If your interest in radio is to be a talk radio star, then amateur radio might not be you, and you should consider looking elsewhere.

Similarly, the transmission of music is also prohibited (with one exception: music incidental to an authorized retransmission of communications from the Space Shuttle is permitted). However, there is reportedly a ruling that one ham singing "Happy Birthday" on the air to another ham does not count as the "transmission of music", presumably because most hams seem to be unable to sing. Again, this is a noncompete regulation; if you want to transmit music the FCC wants you to use the broadcast service or a low power service to accomplish your purpose, not amateur radio. If your interest in radio is to be an on-air DJ, again, amateur radio might not be for you, and you should consider looking elsewhere.

The use of codes, ciphers, encryption, or any other method for concealing meaning is prohibited, with two exceptions that are very similar in nature. A station may use encrypted transmissions for the telecommand of an amateur space station (that is, an amateur station more than 50 kilometers above the earth's service; typically, a satellite, either manned or unmanned), or for the remote control of a model craft (such as a model airplane, boat, or car). In the satellite station case, the FCC mandates that all satellite stations be able to be "remote killed" from the ground, and in any case a malicious operator could easily pervert a satellite's operation by tweaking its control parameters to the point that it could not be recovered. Given the high expense of putting satellites in orbit, and the extreme difficulty in servicing them once they're there, the FCC lets us protect those stations in this way. The same permission is granted for remote control craft for much the same reason; also, telecommand stations for remote control of model craft are subject to power limitations (one watt) that make it unlikely that the remote control transmissions will create difficulties for other stations, and to physical identification requirements that will allow identification of the station operator in the unlikely event that there is unacceptable interference.

Amateurs may not send "false or deceptive signals". This mainly means that amateurs may not use fictitious identification to try to appear to be someone they are not, or to try to get someone else in trouble. It also means that, e.g., false calls of distress are bad (but we've already covered that).

Amateurs may not use indecent or obscene language on the air. This one is probably one of the most violated rules on the bands, sad to say: there's quite a lot of indecent and no small quantity of obscene language on the HF bands (75 meters is especially notorious for this) as well as on VHF and UHF repeaters in many areas. What exactly is meant by "indecent" and "obscene" is complicated, and it's probably best to play on the safe side here, not so much for the sake of not violating the rules, but simply out of respect for not only your fellow amateurs (who may well be very much not like you) but also anyone else who might be listening in. Remember that kids, and even entire classrooms, listen to this stuff sometimes, and your name and address are published by the FCC so (unless you've been making "false or deceptive signals") anyone who does hear you swearing on the air will be able to find out exactly where you live. And that might prove to be embarrassing.

This post has been brought to you by pool questions T2A01, T2A02, T2A03, T2A04, T2A06, T2A07, and T2A08.

The Responsibility of the Amateur Radio Operator

2010-01-16T00:41:00.000-06:00

As the casual reader of this blog has no doubt noted, I have been blogging about the question pools used for the amateur radio examinations in the United States, focusing (so far) on the Technician exam. The NCVEC just announced the 2010 edition of that pool, and I'm going to have to take a look at it soon and comment on it the way I did on the 2008 Extra pool when it was released. However, I want to grouse about a particular question on the old pool first, and I'm going to continue to blog about the old pool for now because that's what people will be testing against until July, at least.

Question T1D08 asks: "What is your responsibility as a station licensee?" and gives (like all other questions on these tests) four choices. Now, of course, amateurs have many responsibilities as station licensees, many (but not all) of which are set out explicitly in the various regulations in Part 97 and elsewhere in Title 47 of the Code of Federal Regulations. Hams are, obviously, required to follow those regulations; this is so blindingly obvious that it almost should go without saying. Which is, I suppose, why the correct answer to this question is "Your station must be operated in accordance with the FCC rules". There is really no excuse for getting this one wrong.

It is worth noting, however, that the other three options for this question are not only wrong, but relatively obviously wrong. "You must allow another amateur to operate your station upon request" is nearly the exact opposite of the real rule, which is that you are never required to let anyone use your station and are responsible for any transmissions by anyone you do let use it. "You must be present whenever the station is operated" is simply not true; there are many situations in which you may be absent from the station or its control point while the station is being operate. And the third, "You must notify the FCC if another amateur acts as the control operator", is dismissable on the grounds that the FCC is certainly not interested in getting constant such reports from amateurs.

I question the merit of questions like this one: they're so easy that anyone with even mediocre test-taking skills can get the answer without knowing anything more about amateur radio than the fact that it's regulated by the FCC. One small bright spot on this: it appears that this question has been dropped from the 2010 pool, although I won't know that for sure until I do the full match-up and comparison.

This post has been brought to you by pool question T1D08.

Renewing your amateur radio license

2010-01-02T02:09:00.001-06:00

So you've had your license now for ten whole years and it's about to expire. Obviously, you're going to want to renew it. The question is, how do you go about doing this?

Well, you have several choices. You can fill out a paper FCC Form 605 and mail it to the FCC. The problem with doing this is that this form is used by the FCC for about a half dozen different services; filling it out correctly is something of a challenge. So don't do that unless you have no other choice.

Second, you can renew through a VEC. The ARRL offers free renewals (except for vanity calls) through ARRL/VEC for its members, and will process renewals for nonmembers for a small fee.

Third, and probably simplest, is to renew online through the FCC's website. Every amateur licensee has been issued a CORES account by the FCC, and using this account information, can log into the FCC's site to manage his or her amateur license (as well as any other FCC licenses that he or she might have). This includes renewals, modifications of the various details on the license such as address or even name, and applications for vanity call signs. The only thing you cannot change via CORES is your license class; that can only be done via a VEC.

If you're like most people, of course, you've not used CORES since you got your license ten years ago (or never, if you got your license before CORES came online in the early 2000s) and so you don't know your password. Don't fret, the FCC will send you a password at your mailing address if you ask them to. (Of course, this assumes you've kept your address current on your license, but you're required to do that anyway.)

The only time the FCC charges a fee to renew an amateur license is if that license was issued a vanity call sign. In this case, to renew the license you must pay a new regulatory fee for a vanity license. If you do not wish to do so, you can first file a modification asking the FCC to issue you a new sequentially-issued call sign, which will convert your license back to a standard amateur license, which you can then renew for free.

You can renew your license beginning 90 days prior to its expiration, and for up to two years after it has expired. If you go beyond the two year grace period, you will have to retest, and you won't be able to get your call sign back, except by using the "former holder" provision of the vanity call sign program (for which you will have to pay a fee).

Remember also that the two year grace period is strictly a renewal-without-retest grace period. If your license expires, you may not operate on the air until the FCC has received, processed, and granted the renewal of your license, as reflected by the FCC's ULS license database.

This post has been brought to you by pool questions T1D06, T1D07, and T1D11.

Who can be a ham?

2009-12-08T12:25:00.001-06:00

There aren't a lot of restrictions on who's allowed to be a ham radio operator, at least in the United States. There's four basic requirements that every person wishing to obtain an amateur radio license from the FCC must meet. The applicant must not be a representative of a foreign government, must have a mailing address somewhere where the United States Postal Service delivers mail, must not be prohibited by from being licensed by the FCC or by court order, and must successfully pass the required examination (or examinations) for the grade of license sought. What's more notable in this list of qualifications is what isn't required: more specifically, there's no minimum age and no citizenship or residency requirements.

There is no minimum age for licensees. The youngest licensee that I've been able to find record of was five; his license was earned back in the days when we still had the Novice exam. With the end of the Novice license, all new licensees must now pass the (somewhat harder) Technician test, which would be somewhat difficult for most five year olds, and the youngest Technician I've ever heard of was nine. (Unfortunately, I can neither find, nor remember, any details about either of these two child prodigies.)

Nor are licensees required to be either citizens or residents of the United States. Resident aliens are just as entitled to have a US-issued amateur license as citizens are, and even nonresident aliens can obtain one if they have an address in the United States at which they can receive mail. (A PO Box or mail drop, or the address of a friend or relative who is willing to forward your mail to you, is sufficient for this purpose.) However, if you do not have a Social Security Number, you will need to obtain a Federal Registration Number (FRN), via the FCC's website, prior to taking the license examinations, or the VE team will not be able to process your application. It's entirely possible to obtain an FCC license without ever setting foot in the United States, although I'm not clear on why one would want to do this.

The FCC does reserve the right to deny a license or license renewal, or to cancel a license, if the applicant or licensee "lacks the requisite character qualifications to be and remain a Commission licensee". This is pretty rare, though, and requires pretty signficant misconduct.

As a side note, there is no prohibition on federal government employees being amateur radio licensees. While no federal agency may obtain an FCC license (federal agencies are required to coordinate their radio activities through the NTIA instead of the FCC), in general nothing prohibits a federal employee from being an amateur radio operator on their own time. Federal employees who may have a reason to use amateur radio frequencies in the course of their duties must be specially authorized to do so by the FCC or by other relevant authority.

This post has been brought to you by pool questions T1D02 and T1D03. Section references above are to Title 47 of the Code of Federal Regulations, browsable via the GPO Access eCFR service.

Operator licenses, station licenses, and licensing-by-rule

2009-12-08T00:18:00.000-06:00

The astute reader will, by now, have noticed that most of the recent articles on this blog have been related to questions on the amateur radio licensing exams used in the United States. This one is no different, but I'm going to get to where I'm going a bit circuitously. Bear with me here, there really is a point to all this.

In the United States, federal law (47 USC §301, the Communications Act) requires that any person who use a device which emits electromagnetic energy for the purpose of communications must do so pursuant to a license issued for that purpose. The FCC issues a large number of different licenses for various different uses; the different categories of license are grouped into what are called "services", which is a term that itself derives from the international Radio Regulations, which govern radio worldwide under the auspices of the ITU (which I've talked about earlier). However, some of these services include things like the Citizen's Band service and the Family Radio Service, which are commonly spoken of as being "unlicensed". How does this make sense, given that the Communications Act requires a license for everyone who uses a radio for communication?

Well, the FCC has a clever way around not bothering with issuing individual licenses to everyone with a CB radio (which they used to do) or FRS radio. The FCC declares that anyone (other than an agent of a foreign government) who possesses (for example) a Citizen's Band radio manufactured in accordance with FCC regulations is, by virtue of possession of that radio, "licensed by rule" to use it for the purpose of communications in accordance with the relevant regulations (in this case, Part 95 Subpart D, §95.401 through 428). As a result, persons licensed in services which are licensed-by-rule do not receive individually identified licenses.

Amateur radio, of course, is not a license-by-rule service; amateur radio licensees are individually licensed and do, in fact, receive individually identified operator licenses. And that's how we come back to the exam questions that I'm writing about: Question T1D01, on the Technician test, gives a list of radio services regulated by the FCC and asks which one is issued an "operator station license". Two of the services listed are "license-by-rule" services: the Family Radio Service and the Citizen's Radio Service. The third, the General Radiotelephone Service, does issue licenses (the General Radiotelephone Operator License, or GROL) to individually-identified persons, but this license does not entitle one to establish a station, only to operate, repair, maintain, or adjust stations already licensed in some other service; such licenses must be independently obtained and maintained. A GROL, or any other license under the General Radiotelephone Service, is an operator license only.

The amateur radio service is unique in that the license grant is a dual grant, both of an operator license and a primary station license, which is what the NCVEC is, somewhat inaccurately, calling an "operator station license" (the actual language in §97.5 is "operator/primary station license grant" and the NCVEC really should, but for some inexplicable reason did not, use the same language in the question as in the regulation). So this question, as inartfully worded as it is, is really testing on whether one understands the duality of the license grant in the amateur radio service, and (for that matter) if one recognizes that the amateur radio service is, in fact, called the "Amateur Radio Service". Not the best question, I must admit. I have to wonder if it'll be carried forward into the next version of the pool.

This post has been brought to you by pool question T1D01. Section references above are to Title 47 of the Code of Federal Regulations, browsable via the GPO Access eCFR service.

Keeping the "amateur" in amateur radio

2009-12-07T15:12:00.001-06:00

I've talked quite a bit about what you can do on ham radio here. This post will talk about the restrictions that prevent the commercialization of amateur radio: things you cannot do on ham radio.

The first restriction I want to talk about is the prohibition on the use of ham radio "on a regular basis" for communications that "could reasonably be furnished alternatively through other radio services" (§97.113(a)(5)). This is basically the "noncompete" rule: the amateur radio service is not permitted to compete with or displace commercial radio services (for which the FCC collects licensing fees, some of which are quite substantial). In practice this rule is impossible to enforce, and would only be enforced in the most egregious of cases. However, hams should consider whether any proposed long-term ongoing use of amateur radio frequencies might be better accomplished in one of the other radio services, especially when the intent of that ongoing use is not very much in keeping with the basic purposes of the amateur radio service.

A more significant set of restrictions are the prohibitions on the use of amateur radio to facilitate commercial gain. There are basically two of these in the FCC rules. First, no amateur station may transmit any communication in which either the station licensee or the control operator has a "pecuniary interest"; this includes transmissions made on behalf of an employer (whether or not specific compensation is received). You may not operate a business (either your own or your employer's) via amateur radio, even if your business is related to amateur radio. You're not allowed to use ham radio frequencies to communicate with or about other employees of the business, with or about customers or vendors of the business, or with or about potential customers or vendors. The only exception to this rule is that you may use amateur radio to notify other amateurs of the availability of equipment for sale or trade (so-called "swap and shop" traffic), provided such communications are not conducted on a regular basis. If you're working on your friend's radio for him and he has promised to pay you for your time and effort when it's ready, you may not call him on the local repeater to tell him it's ready, as that would be a communication in which you have a pecuniary interest. But if you have a radio you're willing to trade or sell, you may use amateur radio to attempt to find someone willing to buy or trade for it, and consummate the transaction via amateur radio, provided you don't do this on a "regular basis".

Second, you cannot be paid to operate an amateur radio station (with two very limited exceptions which I won't cover here; they're found in §97.113 if you want to look). This has created some controversy of late because many local and state governments, as well as private entities that provide emergency services such as hospitals, have encouraged their employees to have and use amateur radio equipment for emergency communication purposes. The FCC recently issued a public notice clarifying this regulation: such employees may not use amateur radio while "on the clock" except in an actual emergency. The FCC has provided a waiver process for agencies who wish to allow their employees to participate in drills involving the use of amateur radio frequencies to obtain a waiver of this rule for the purpose of that drill. So far one such waiver has been applied for and approved, for a drill in Kentucky. A question I don't have an answer for yet is whether the Illinois indemnity and loss compensation scheme for volunteers accepted into service to the state during a disaster constitutes "employment" for the purpose of this rule.

This post has been brought to you by pool questions T1C11, T2A09, T2A10, T2A11, T2D04, G1B09, E1F10 and E1F11. Section references above are to Title 47 of the Code of Federal Regulations, browsable via the GPO Access eCFR service.

Hamming internationally

2009-12-06T12:43:00.001-06:00

Historically, one of the major appeals of ham radio was the opportunity to use amateur radio to talk to people in far-off lands. While the Internet and cheap international long distance has cut into this somewhat, it's still a significant draw of the amateur service, and in fact building international goodwill is an explicit purpose of the amateur radio service (§97.1). Radio signals have a nasty habit of not respecting national boundaries, and as all of the HF bands have at least long-range if not world-wide propagation at least some of the time, it's very likely that any ham with HF privileges will at some time be involved in a conversation with someone in another country; even someone without HF privileges has a decent chance of it. The availability of direct, personal international communications via ham radio has been quite controversial historically, and some of the special rules that apply to international communications can be clearly tied to the geopolitical history of the 20th century.

The general rule for international communications for amateur radio operators is that they are allowed. However, if the national communications authority of either country involved has notified the ITU that it objects to international amateur radio communications, then the communication is prohibited. The United States does not currently ban any countries, and at the present time there are, in fact, no banned countries.

In addition, all international communications must be "limited to communications incidental to the purposes of the amateur service and to remarks of a personal character" (§97.117). This is much more restrictive than the rules for domestic amateur radio communications. The main purpose of these restrictions is to prohibit communications of a political nature, and it is, in fact, a very bad idea in many countries. Communications of a political nature are permitted in the US (although many of us believe they should be discouraged), but they are, in fact, forbidden across national boundaries and hams would be well advised to avoid them.

In addition, when operating internationally there are limits on your authority to forward messages on behalf of others (so-called "third party communications"). Third party communications (messages forwarded for people who are not themselves amateur radio operators) are limited to the same terms mentioned above regarding content. In addition, the general rule for third party communications is that they are prohibited except when specifically authorized, except for emergency and disaster relief communications. So, while amateurs have the presumptive right to chat with one another, they do not have a presumptive right to pass messages for third parties. Passing messages for third parties requires that a "third party message agreement" be in effect between the countries involved. The United States presently has such agreements with about four dozen countries; the current list can be found on the FCC's website. It should be noted that virtually none of Europe is on this list: third party traffic to European stations is generally prohibited. This rule also applies to the situation where a nonlicensed person participates in the sending of a message (usually, by allowing someone other than a licensed amateur talk into the microphone). In other words, if you're in the US talking to a ham in Germany, you may not put your kid on the radio unless your kid is also a licensed ham (the third party rule does not apply if the third party is eligible to be the control operator of the transmitting station).

Another small note: when operating internationally (or domestically, for that matter) it's perfectly acceptable to carry out the conversation in a language other than English. However, you are required to identify in English, even if the conversation is progressing in some other language. The internationally-standardized NATO phonetic alphabet, which is encouraged in the amateur service anyway, counts as "English" for the purpose of this rule (which is, for the record, §97.119(b)(2)).

This post has been brought to you by pool questions T1C10, T2B07, T2D05, G1E05, G1E07, G1E08, G1E09, G1E10, and E1F16. Section references above are to Title 47 of the Code of Federal Regulations, browsable via the GPO Access eCFR service.

Getting along with others: Primary and secondary allocations

2009-12-05T18:43:00.001-06:00

There is a general rule of radio operation that says that a station is entitled to operate free of harmful interference from other stations in the same or other services, and at the same time all stations are obliged to operate so that they does not interfere with other stations in the same or other services. Stations that suffer harmful interference from other stations are generally entitled to relief from such interference; that is, the national administration responsible for supervising the interfering station is generally obliged, under law or treaty, to take steps to cure the interference, if the interfering station doesn't do so first. However, this rule is a very general one, and (like most rules) is subject to some exceptions. This post is about one of those exceptions: the system of primary and secondary allocations.

I've mentioned the ITU a few times now, and that one of their major responsibilities is frequency management. One of the things that the ITU, and also national regulators such as the FCC, do in furtherance of this is sometimes allocate a band to more than one use. When they do so, they will typically designate one of those uses as "primary" and the other(s) as "secondary". When a band has been designated with both a primary allocation and a secondary allocation (either by the ITU or by the FCC), this modifies the general rule regarding cross-service interference. Specifically, a station in a service which has a secondary allocation in a particular band has no right of protection against interference, harmful or not, from stations in a service which has a primary allocation in that band. Such stations, more succinctly referred to as "secondary stations" in §2.105(c)(2), must at all times yield to primary stations and take steps to avoid interference.

Many of the bands allocated to amateurs are also allocated to other services. For example, the entire 70cm UHF band (420-450 MHz, in the United States) is a secondary allocation for amateurs; the primary allocation is federal and the principal user is the military, who mainly uses this band for various radar systems, most notably the PAVE PAWS early warning system deployed at Beale AFB and at Cape Cod AFS (which leads to limitations on the use of the 70cm band for hams in proximity to either of these sites). Another band for which the amateur service is a secondary allocation is the 60 meter HF band. The 60 meter band is channelized and is the only band on which an amateur may not transmit Morse code. It is shared with the federal government (the primary user) and amateurs must immediately cease operation if interference is caused with a federal station.

The situation with the 30 meter band is even stranger. While 30 meters is primarily allocated to hams by the FCC, that allocation is only valid within the United States and its outlying insular regions. Outside that area, the 10100–10150 kHz band is allocated primary to the fixed service, and a footnote (footnote US247) to the Table of Frequency Allocations (§2.106) states that "[t]he band 10100–10150 kHz is allocated to the fixed service on a primary basis outside the United States and its insular areas. Transmissions from stations in the amateur service shall not cause harmful interference to this fixed service use and stations in the amateur service shall make all necessary adjustments (including termination of transmission) if harmful interference is caused." Because 30 meters has worldwide propagation (and in fact is one of the most interesting bands there is in terms of propagation), interference is pretty easy here, which is probably part of why hams in the US are limited to 200 watts in this band (instead of the more usual 1500), and why this band is the only amateur band with no voice privileges anywhere within the band. (I've yet to find out the specific, historical reason why this band has this rather unusual noninterference restriction and to what purpose the other fixed stations in this band used it or if they're still there. If anyone knows, please do let me know.)

This post has been brought to you by pool questions T1C09, G1A14, and G1A15. Section references above are to Title 47 of the Code of Federal Regulations, browsable via the GPO Access eCFR service.

How long is your band?

2009-11-08T22:28:00.001-06:00

When talking about frequency, and especially about "bands" (divisions of spectrum made for the purpose of allocation), it's very common to see frequencies specified in units of length (meters and centimeters being most common) instead of in units of frequency (kilohertz, megahertz, or gigahertz, or, more archaically, kilocycles or megacycles). When a length unit is used, it specifies the wavelength involved. The wavelength of a light wave is, of course, directly related to its frequency: the wavelength is the distance the wave travels (at the fixed speed of light) over the period of one oscillation, and so wavelength is just speed divided by frequency (and frequency is speed divided by wavelength).

Fortunately, the math for this is pretty simple, especially in the metric system (which even us backward Americans use when doing ham radio, thankfully). By pure serendipity, the speed of light (in a vacuum) is approximately 299,792,458 meters per second; this is close enough to 300,000,000 meters per second that for most purposes the latter value can be used. So to convert a wavelength in meters to a frequency in megahertz (or vice versa), one must merely divide 300 by the wavelength (or frequency). Hams routinely refer to all the amateur bands below 200 MHz by their wavelength instead of their frequency, and it's quite common to hear the higher frequency bands by wavelength as well, so it's important to be able to do this translation on the fly (at least until you memorize the more common ones). Fortunately, dividing into 300 isn't that hard.

So when a ham talks about the "160 meter band", they're not talking about a really long parade; instead, they're talking about a band whose wavelength is approximately 160 meters, which corresponds to a frequency of about 1875 kHz. The 160 meter band is actually 1800 to 2000 kHz, so this is pretty close. Other examples (more pertinent to the student preparing for the Technician exam) include the 6 meter band (50 to 54 MHz), the 2 meter band (144 to 148 MHz), the 1.25 meter band (222 to 225 MHz), the 70 centimeter band (420 to 450 MHz), and the 23 centimeter band (1240 to 1300 MHz). Please do note also that these band definitions apply only in ITU Region 2 (and obviously only in the United States or other places where the FCC regulates amateur radio), and that other restrictions based on location may also apply (especially with respect to the 70 centimeter band, which has a lot of interesting restrictions on it).

Of the questions on the Technician exam related to this, two (T1C04 and T1C06) present an additional challenge that cannot be resolved simply by dividing into 300, as there are incorrect answers that are "close enough" that you can't eliminate them based solely on approximate wavelength. Therefore, it's very important that you commit to memory the limits of the 6 meter, 2 meter, and 70 centimeter bands given above, not only for the purpose of passing the exam but also for the purpose of responsible operation.

This post has been brought to you by pool questions T1C04, T1C05, T1C06, T1C07, and T1C08.

Mayday, mayday, mayday: Emergency operations

2009-11-08T20:35:00.001-06:00

Quite a lot of people get into amateur radio for the purpose of emergency communications. There are two meanings to that phrase, too, and it's important to keep them straight. The first, "emergency communications", is the provision of communication assistance during an "emergency"; that is, responding to a station in distress and, based on the ensuing communication, providing assistance directly or dispatching others to provide assistance. The second is more strictly a "communications emergency", which is when an emergency situation cause (or is likely to cause) a failure or breakdown of ordinary communications systems. Amateur radio operators have specific powers and duties in both of these situations. Providing emergency communication is one of the declared purposes of the amateur radio service, so hams should have some understanding of these powers and responsibilities.

Amateurs are, generally speaking, not permitted to communicate with stations in other services using their amateur radio station. This includes the licensed-by-rule Family Radio, General Mobile Radio, Citizen's Band, or Multi-Use Radio services. Even though all of these services are available to anyone (other than a representative of a foreign country) who possesses the appropriate equipment, hams are not exempted from the requirements in these services to use type-accepted equipment and hams who wish to operate in these services must ordinarily meet these same equipment limitations and requirements as any non-ham would. Nor may a ham use his or her equipment to communicate with public safety entities. There are, of course, exceptions to this general rule, almost entirely for emergency situations.

There are three major exceptions for "emergency" situations: First, an amateur may use any means of radiocommunication at his or her disposal in order to provide essential communications needs during an emergency which immediately threatens human life or property, when other forms of communication are unavailable or disrupted. Second, an amateur station which is actually in distress ("distress" also being a term of art which in this case means "in immediate threat of loss of life or serious permanent injury") may use any means at its disposal to attract attention and obtain assistance. Third, an amateur station who is aware of a station in distress may respond to that station in distress or make any other communications necessary to obtain assistance for that station in distress, even if that would involve transmitting to stations outside the amateur service or using frequencies not authorized to the amateur.

These exceptions are to be construed very narrowly, in practice. The communications must be "essential", the threat to life or property must be "immediate", and other forms of communication must be "unavailable". Don't use this one lightly; if you have a choice between running next door to use their phone to call 911 or transmitting on the local fire department's general frequency, please go next door and call 911. This is intended as an absolute last resort "when all else fails", not an option to used when other options are merely inconvenient. Similarly, if you are monitoring, say, the marine HF bands and you hear a Mayday call, do not immediately respond; you might interfere with other ships or the Coast Guard responding. Only if you do not hear a response, or if the calling station repeats the call (instead of responding to a response to their Mayday call) should you "unlock" your gear and respond to the calling station, or relay the call.

In addition, the FCC may declare a "communications emergency" when a disaster causes the loss of normal communications in an area. During such a declaration, amateurs must refrain from using any frequencies designated in the disaster declaration unless they are actively involved in providing assistance. Such declarations are common during major disasters, such as hurricanes and earthquakes, which tend to disrupt normal communications. The FCC may also authorize amateurs involved in providing assistance to use frequencies other than those which are normally available to amateurs, or to communicate with stations not in the amateur service, during a communications emergency; amateurs are required to comply with the directions of the FCC and its Field Engineers in such situations.

Outside of an FCC declaration of an emergency, no frequencies are reserved for emergency communication; there is no amateur equivalent of CB channel 9 or marine channel 16. In general, the best frequencies to use for declaring an emergency in the amateur bands would be the various national calling frequencies, because there's a better chance that someone will be listening on one of these. However, emergency traffic always takes priority over non-emergency traffic, on all frequencies and at all times.

It should go without saying that if you hear a station calling with an emergency (for which the most proper method to call "Mayday" three times, followed by identification) any non-emergency communications on the same frequency must immediately suspend until the emergency is resolved. At the very least, do not interfere with emergency communications, and to the extent that you are able, you should assist the station in distress. (But avoid creating confusion; listen closely and think before you transmit.) You should always assume that a declaration of emergency is real; if it's not, the station calling the emergency is the one on the hook for making a false distress call. In the United States, making a false distress call is a federal felony; offenders will almost certainly lose their FCC licenses, and will face stiff fines (in one recent instance, $45,000) and even the possibility of prison time, so don't do that.

This post has been brought to you by pool questions T1C03, T8A01, T8A02, T8A03, T8A04, T8A06, T8A08, T8A09, T8A10, T8A11, T8A12, T8B08, T8B11, and T8C01.

What's in a call sign, anyway?

2009-11-05T01:56:00.000-06:00

Most people have some familiarity with call signs, if nothing else from broadcast radio stations, which in the US tend to be four letters starting with either K or W. The more knowledgeable will know that in the broadcast services, K stations are west of the Mississippi and W stations east of it (with some grandfathered exceptions). Those near the borders may know that Canadian stations start with a C, and Mexican stations with an X. But, unless you're a shortwave listener or a ham, you probably don't know why the letters used are K and W, or what other letters might be used for, if anything.

The ITU, which I talked about in my last post, is the entity that makes the rules that everyone has to follow for call signs. Each member country is assigned one or more one or two character prefixes (or, in two cases, three character), and all call issued by that country have to start with one of those prefixes. There are nine one-character prefixes: B, F, G, I, K, M, N, R, and W; the United States, being a charter member of the ITU and the largest at the time that it was decided to regularize call signs, got three of them; (N, K, and W); the UK gets two (G and M), and the other four go to China (B), France (F), Italy (I), and Russia (R). Everyone else has to use at least two characters for national identification; Canada, for example, is allocated CF through CK, and Mexico is allocated XA through XI. (Both countries have other allocations.) Some countries even have prefixes that start with digits instead of letters.

So why N, K, and W for the US? France, Italy, and Russia got their initials, after all. Well, during the early years the US military used A call signs for Army stations and N call signs for Navy stations. W (. - -) and K (- . -) are what you get when you add a dah to the Morse code for A (. -) and N (- .), and so commercial stations adopted those letters. The United States has since given up part of A for the use of other nations, and now only has AA through AL (in addition to all of W, K, and N).

In addition to allocating prefixes to the many member nations, the ITU also sets standards for the parts of the callsign after the prefix, at least in certain services. For amateur radio stations, the ITU mandates a one or two character national prefix, then a digit, and then up to four additional characters, the last of which must be a letter. For the United States, which has three one-character prefixes, that means a callsign can be as short as three characters or (in theory) as long as 7. The FCC, however, does not issue four-character suffixes yet, and reserves the so-called "one-over-one" callsigns (one letter, one digit, and one more letter) as "special event stations" (which are issued for short-term use by any ham who requests and obtains one from the NCVEC, who administers that program, and never permanently), so all FCC-issued amateur call signs are four to six characters long. Not all combinations within this space are used, either; the FCC excludes for the moment all "two-over-three" (two letters, one digit, and three letters) call signs beginning with A and N from the amateur service, and excludes certain others combinations for a variety of other reasons. Also, while the ITU regs would allow for the issuance of a call sign containing more than one digit, the FCC does not do this; US amateur call signs always contain exactly one digit. And that digit is not entirely without meaning.

For the purpose of the amateur radio service, the FCC divides the country into 13 regions. The first 10 regions, numbered 1 through 9, and 0, are groupings within the "lower 48" (see map to right). Regions 11 through 13 are Alaska; Puerto Rico and other Caribbean islands; and Hawaii and other Pacific islands. The FCC issues call signs based on what region the amateur's mailing address is in, and within each region based also on the amateur class of license, using what is called the sequential call sign system. For those in regions 1 through 10, the digit in the call sign corresponds to the region number; for regions 11, 12, and 13 the digit used also depends on location (typically, which island you're on). Every amateur gets a sequentially-issued call sign initially; after that a ham's call sign will only change (barring extraordinary events) if the amateur, applies for a vanity call sign or requests a new sequentially-issued call sign. Also, once the FCC has issued a call sign, it will never issue it again via the sequential system; the only way for a call sign that has been abandoned to be used again is via the vanity call sign system.

In addition to dividing the country into 13 regions, the call signs available in each region are further divided into four groups, A through D. Calls in Group A are reserved only to Extras; those in Group B are available to Extras and Advanceds; those in Group C to everyone except Novices; and those in Group D are available to any amateurs. Because of this, you can tell from a call sign what the minimum license class someone has: someone with a two-over-one or a one-over-two is necessarily an Extra. But you cannot assume that someone with a two-over-three is a Novice (and in fact that's almost certainly not the case), for three reasons. First, a ham who upgrades does not automatically get a new call (anymore; that used to be different), and so could have a higher license class than his or her call sign group indicates. Second, a ham may request any call sign which is permitted to his or her license class through the vanity program. The third, and perhaps most common, for call signs that don't fully reflect the licensee's operating class is that Group C is exhausted in almost all regions, which means new General and Technician licensees (in the lower 48, at least) now get two-over-three "Novice" calls (as do initial club licenses, which are applied for through Club Station Call Sign Administrators, instead of the usual VE process).

This post has been brought to you by pool questions T1B03, T1B04, T1B05, T1B06, T1B08, T1B09, and T1B10.

Thinking regionally

2009-10-28T00:10:00.001-05:00

I mentioned the ITU briefly in my last post; I'll talk a bit more about this nebulous entity here. The International Telecommunication Union, or ITU, is a multinational treaty organization established by a multilateral treaty that has been acceded to by almost all of the world's nations; the United States is one of the charter members. The ITU makes rules for radio operation (and especially frequency allocation) that all member nations agree to respect. As radio signals have a bad habit of refusing to stop at national boundaries, this is pretty much necessary, especially with respect to the world-reaching HF bands, in which a station in South America can easily interfere with a station in Russia.

For the purpose of aiding frequency management, the ITU has divided the world into three regions, named (unsurprisingly enough) Region 1, Region 2, and Region 3 (see map). Roughly speaking, Region 1 is Europe and Africa, Region 2 is North and South America, and Region 3 is Asia (excluding Asiatic Russia) and Oceania. The allocation of frequencies to the various services that a treaty member may make varies by region, mainly due to historical reasons but also due to different technological paths that were taken in different parts of the world. A full discussion of the details of the differences would be quite long; fortunately, hams don't need to know most of it.

The main situation in which differences in ITU region allocation has an impact on US hams is in 40 meters; the Region 2 allocation for the 40 meter amateur band is 7.000 to 7.300 MHz, while in Region 1 it's only 7.000 to 7.200 MHz and in Region 3 it's only 7.000 to 7.100 MHz. To make matters worse, many of the frequencies that are not allocated to hams in these regions are allocated to broadcasters. Since 40 meters is a worldwide band (much of the time), this creates a good deal of opportunity for interference. In addition, the subbands reserved for CW and data in each region are different, and until recently it was actually legally impossible for a US ham in Region 2 to have a phone QSO with a Region 1 ham on the same frequency (as the US phone subband doesn't start until 7.125 MHz, which was above the entire Region 1 40 meter amateur allocation). US hams wishing to work Australia, and until recently Europe, on 40 meters phone have to resort to "split operation", in which one station transmits on one frequency authorized to his use (but not to the use of the station he is calling), and the other station then responds on a different frequency that is within his authorization. The frequency pair to be used would either be agreed on by prior arrangement, or indicated in the initial call by specifying "split" and the frequency on which a response was expected (or sometimes by using "up" or "down" and the difference between the transmit and receive frequencies).

The astute reader will notice that just about all of the United States is in Region 2 (a tiny bit of US territory—Guam, American Samoa, and the Marianas—is in Region 3). However, §97.301 shows separate listings not only for Regions 2 and 3, but also for Region 1, even though no part of the United States is in Region 1. Why is this? Because of the "ship at sea" provision: FCC regulations apply to any person who wishes to operate as an amateur onboard a US-flagged ship while that ship is in international waters, no matter where in the world that might be. So if you're ever on a transatlantic cruise, and you've taken your ham radio along (and gotten permission from the ship's captain to operate, which actually isn't that hard to get), you'd better keep track of where the ship is; when it crosses over that line you may have to change your operating frequencies. (Of course, you have to keep track of where you area anyway, bceause once you enter the national waters of another country you become subject to that nation's rules.)

This post has been brought to you by pool question T1B02.

Please do not interfere, we're busy here!

2009-10-27T16:48:00.001-05:00

Interference is a frequent problem in all radio services, and the amateur service is no exception. Interference is anything (natural phenomena, other signals, whatever) that hampers or prevents the successful receipt of a radio communication by its recipient other than the simple lack of a signal path between the transmitter and the receiver. Hams distinguish between natural sources of interference (often called "atmospherics" or "QRN"), which are typically caused by things like lightning storms or coronal mass ejections hitting the magnetosphere, and artificial sources of interference (or "QRM"), which may be the result of other people's attempts at transmissions, deliberate jamming, or noise produced by noncommunicative uses of RF energy (like microwave ovens, computers, and hybrid cars).

The exact definition of interference can be found in 47 CFR §2.1(c): "The effect of unwanted energy due to one or a combination of emissions, radiations, or inductions upon reception in a radiocommunication system, manifested by any performance degradation, misinterpretation, or loss of information which could be extracted in the absence of such unwanted energy." As this regulation is taken directly from the ITU's Radio Regulations, this definition is effectively universal across the world. The International Telecommunication Union, or ITU, is the international treaty organization that regulates radio worldwide; the United States is a member nation of the ITU, as are virtually all other countries in the world. (An important side note here: while the regulations that apply to amateur radio specifically appear in Part 97, hams are also required to comply with the general regulations that appear in Parts 1 and 2, and reference to these parts sometimes clarifies matters that are left unclear by Part 97 standing alone. Some familiarity with these parts, as well as with Part 97, is therefore a good idea for the conscientious ham.)

I'm writing this series of posts at least in part as an effort to discuss the questions on the various exams. And in this one I've come to a question that I disagree with the NCVEC about. The question in this case is T1A10, which I here quote in full:

What is a transmission called that disturbs other communications?
A. Interrupted CW
B. Harmful interference
C. Transponder signals
D. Unidentified transmissions

The NCVEC considers the correct answer to be "B", "harmful interference". However, the FCC explicitly defines "harmful interference" (in §97.3(23)) as "Interference which endangers the functioning of a radionavigation service or of other safety services or seriously degrades, obstructs or repeatedly interrupts a radiocommunication service operating in accordance with the Radio Regulations." (This same definition is found in §2.1(c) and also derives from the ITU Radio Regulations.) The FCC's definition requires more than just a simple "disturbance" of communications for a transmission to be "harmful". In this case, "B" is the "most correct" answer, but it is not a correct answer, simply because not all transmissions that disturb other communications will qualify as "harmful interference", merely as "interference".

This post has been brought to you by pool questions T1A10 and T1B01.

If it's a "station", how come it can move?

2009-10-26T21:39:00.001-05:00

An amateur radio station is defined (by regulation) as "the apparatus necessary for carrying on radiocommunications". In other words, the station is the radio (transmitter and, as appropriate, receiver), feedline, antenna, and presumably also power supplies and other mechanical appurtenances required to enable all that to work together for the purpose of communications via radio. The station does not include the operator, and stations are technically licensed separately from operators, although this is very much not obvious anymore.

Despite the name, "station", nothing about this definition of a station requires that the station be stationary, at least in the amateur service. Older hams will remember the "mode" suffixes of "mobile" (/M), "portable" (/P), "maritime mobile" (/MM), and "aeronautical mobile" (/AM), which used to be required whenever an amateur was operating a station that was not at that amateur's primary station location. The FCC no longer restricts amateurs to a single primary station (we're allowed to have as many primary stations as we want now without obtaining additional license grants, which is why amateurs are now restricted to one and only one amateur radio license per person), and no longer requires the modal suffixes, but it doesn't hurt to know what these mean because they are still commonly used (and occasionally misused), and furthermore they are sometimes still required when operating outside the United States on a reciprocal treaty grant.

"Mobile" is defined as "operating a station which is capable of being operated while in motion". Therefore, one is "mobile" when operating a station installed in a car, motorcycle, or bicycle. It also applies when using a handheld transceiver (since you can operate a handheld while wilking), although many people incorrectly use "portable" for this. There are two special sub-cases of mobile: operating while on a boat is "maritime mobile", and operating from an aircraft is "aeronautical mobile"; in both of these sub-cases permission of the master of the boat or the pilot in command of the aircraft is required, and your station must be independent of the craft's own radio equipment (except that you may share an antenna with a boat's radio systems, but not an aircraft's). (Additional conditions apply; see §97.11.)

"Portable" is defined as "operating a station which has been temporarily installed in some location other than the licensee's primary station location". Since amateur licensees no longer have a defined primary station location, the "portable" designation no longer makes sense, and so some people have (as I note above) co-opted it for the case of operating a handheld. An example of "portable" operation would be a transmitter running off a battery into a longwire temporarily thrown up into a couple trees at a public park.

There's several other modes of operation (the so-called "special operations" that are set out in Subpart C of the regulations), but I'll save those for a subsequent post.

This post has been brought to you by pool questions T1A09, T2C02, and T2D07.

Amateur Radio and the FCC

2009-10-26T12:32:00.001-05:00

The need for at least some top-down regulation of radio, and of amateur radio specifically, should be somewhat obvious. Radio spectrum is limited, of course, and it's very difficult if not impossible for two stations to share the same frequency, at least within the same geographic area. In the very early days of radio, of course, there was no government regulation of radio, and stations did whatever they wanted. Once radio went commercial, in the early part of the 20th century, stations started to interfere with one another, and before long there were lawsuits being filed, typically in state courts under various property law theories. It quickly became obvious that judicial regulation of radio would become untenable. Other problems included amateur radio operators who interfered with ship-to-ship, ship-to-shore, and military communication. The issue came to a head in the public eye with the 1912 sinking of the Titanic; the federal government responded by requiring the licensing of amateurs, prohibiting amateurs from operating in commercial or military frequencies (amateurs were restricted to operating only on the "useless" high frequency bands; at this point skip had not been discovered) and giving minimal regulatory authority to the Department of Commerce. In 1927 this authority was expanded and transferred to the Federal Radio Commission, and in 1934 to the Federal Communication Commission, or FCC, where it remains today.

The FCC has regulatory authority over all uses of radio frequency energy for communication purposes within the territory of the United States and the coastal waters thereof, as well as ships at sea sailing under the flag of the United States, except for use by instrumentalities of the federal government itself (which is separately managed by the National Telecommunications and Information Administration, or NTIA, another federal agency). The FCC also has some jurisdiction over noncommunicative use of radio frequency energy, to the extent that such usages might possibly interfere with communicative uses. (The Department of Health and Human Services, via the Center for Devices and Radiological Health, a division of the FDA, also has some jurisdiction over devices that use or emit electromagnetic energy, but their jurisdiction is concerned entirely to health and safety aspects.) Since amateur radio amounts to the use of radio frequency energy for communication purpose, it falls within the scope of the FCC's jurisdiction, and the FCC is the principal source of the regulations that apply to amateur radio in the United States. Amateurs must also be aware of restrictions imposed by NTIA, since many amateur frequency allocations are shared with various federal (including military) uses.

An amateur license issued by the FCC is valid for use anywhere where the FCC has jurisdiction. Unlike most of the other licensed services, amateurs are not required to declare their station locations to the FCC; we are free to pick up and move whenever we want without notice to the FCC. (This used to not be the case; the FCC used to require that amateurs could only operate from their fixed station location which had to be reported to and specifically licensed by the FCC.) The FCC only requires that an amateur keep the FCC notified of his or her current mailing address so that the FCC may contact him or her if it should need to do so. If the FCC sends you mail and it comes back undeliverable, your license may be suspended or revoked, so it's a good idea not to let this happen. Also, due to a rather large and complicated system of treaties, an FCC-issued license is also valid for use in many other countries, although many conditions and restrictions apply and the amateur should carefully research the relevant regulations and conditions before operating outside the United States under the authority of a treaty grant.

In general, the FCC takes a pretty light hand in regulating amateur radio. This is partially because the amateur radio community is pretty good at regulating itself. However, it's probably more because the FCC is (like many federal agencies) required to meet the bulk of its budget out of user fees. The nearly three decades of experience of having federal agencies self-fund out of user fees has shown us that when this is done, users who pay large fees get more attention from the regulator than users who pay small fees. Amateur radio operators pay no user fees to the FCC (except for vanity license fees, which are entirely optional), so the share of the agency's attention we get this way is very small. And, of course, amateur radio doesn't have a lot of lobbying power, either, which is the other factor that determines the amount of attention an agency spends on an issue. As a result, amateur radio is typically a very small piece of the FCC's attention at any time. The FCC is simply not going to spend a lot of effort (that is, money) on monitoring amateur radio operators for compliance, or dealing with issues that involve only the amateur radio service; it's not worth it to them. At the same time, it's very important that amateurs avoid creating problems with the holders of more lucrative licenses; we don't want to set up a conflict between amateur radio operators and someone with a lot of financial and political power, because that's a conflict we have a very good chance of losing. Basically speaking, amateur radio continues within the larger scheme of radio at sufferance; it's in our best interest not to create too much trouble.

This post has been brought to you by pool questions T1A07, T1B07, T1C02, T1D04, T1D09, T1D10, and T1D12.

The Certificate of Successful Completion of an Examination

2009-10-22T10:49:00.001-05:00

I left this topic out of my previous post because it wold have lengthened it considerably and made it too dense for a single post that was already getting overly long and dense anyway. The document that a VE team gives to someone who has successfully completed a licensing exam is called a Certificate of Successful Completion of an Examination, which is such a hideously long phrase that everyone simply calls them CSCEs. There are an inordinately large number of rules and, more importantly (at least to the person seeking a license), exam questions related to these documents, which used to be much more important than they are today. I would hazard to say that the amount of testing related to these documents more reflects their historical importance than their (much smaller) current importance. The reduction of importance is the consequence of two things: the simplification of the licensing system (which I talk about more here) and the deployment of ULS (which I discuss to some degree here).

At the time the VE system was introduced, there were five levels of license and every license required the successful completion of at least two exam elements (at least one theory element and one Morse code element). The CSCE is the answer to the situation in which one passes some, but not all, of the elements required to qualify for a given license. Instead of having to retake all these elements, the partially-successful examinee is given a document, a "certificate of successful completion of an examination", that certifies that he or she successfully completed an examination. This document is good for 365 days (note that that's 365 days, not one year; if a leap day intervenes the document is good for one year less one day) and, if presented at an exam session at a date not more than 365 days in the future, will result in the examinee being given credit for that previous successful pass without retaking the exam. This meant that if you should flub the theory test but pass the code, test, or vice versa, your day (and testing fee) wasn't a complete waste; you cold go home, bone up on whatever you missed, and try again without having to go through the whole process from scratch. The CSCE is issued to any examinee who passes any element, whether or not the examinee qualified for a new license or upgrade at that session.

CSCEs also served two other purposes (one of which still obtains). First, a CSCE which attests the successful completion of all the elements required for an upgrade of an already-licensed amateur entitles the bearer to operate with the privileges of that new class for up 365 days (or until the FCC either issues an upgraded license or notifies the licensee that the upgrade is being declined for some reason). Before ULS, this was a big deal: it could take a month or more for an upgrade to post to the FCC system and for the FCC to mail back confirmation of the upgrade. Waiting months to use newly-earned privileges was deemed unacceptable. However, upgrades post now in typically under a week, and so the window in which a newly upgraded ham has to use the upgrade-indicating call sign suffixes (/KT for a recently upgraded Technician, /AG for a recently upgraded General, and /AE for a recently upgraded Extra, required whenever one is using frequencies that are available to the operator by virtue of the upgrade and the upgrade has not yet been processed by the FCC) is now typically quite short.

The other purpose that CSCEs used to serve was as evidence of the pseudo-upgrade from Technician to Technician Plus. A CSCE for the 5 word per minute Morse code element (regardless of date; the CSCE could even predate the Technician license) combined with a Technician license entitled the holder to Novice privileges on HF. This was the sole exception to the 365 day rule for CSCEs; such a CSCE was good for the life of the underlying license. This is partially because the FCC didn't (at first) treat this as an upgrade and so no record of the completion would be sent to the FCC. Fortunately, this all went away in 2007, when the Technician Plus license was folded back into the Technician license and Morse code competency testing became a thing of the past.

We still issue CSCEs for successful examinations, of course, and they still have the purpose of authorizing an upgraded licensee's newly-earned privileges during the short period it takes the FCC to process the upgrade. And in the unlikely event that someone were to pass, say, Element 3 but fail Element 2, we can still issue a CSCE for just Element 3. However, that's extremely unlikely to happen; VEs are discouraged from allowing examinees from taking elements out of order, mainly because it doesn't make a lot of sense. One can only wonder if we'll be simplifying this process in the future, or if the NCVEC will be reducing the number of questions related to this process on the exams in the next round of revisions.

This post has been brought to you by pool questions T1A05, G1D01, G1D03, G1D06, G1D08, and G1D09.

The Volunteer Examiner System

2009-10-21T23:05:00.001-05:00

Prior to 1982, examinations for amateur radio licenses were conducted by the FCC directly; candidates had to travel to an FCC office (which might not be that close) at times set by the FCC (which might not be that convenient) and take the test in front of an FCC examiner in a government office. (In some cases it was possible to obtain an introductory license through a field examination, but such licenses were probationary, typically nonrenewable, and in some cases not upgradeable, meaning the licensee would have to retake the same test when they sought to upgrade.) With the election of Ronald Reagan came cost-cutting measures throughout the entire federal government; one of these consequences was that the FCC was forced to consider eliminating the amateur radio program because it could no longer afford to foot the bill for conducting examinations of amateur radio licensees.

Enter Senator Barry Goldwater. Senator Goldwater (formerly K7UGA) had been an avid ham for years at this time, and was also a very influentual member of Congress. He authored and pushed through the law that established the Volunteer Examination (VE) system for amateur radio licensing, in so doing sparing amateur radio from what would otherwise been almost certain death at the hands of Reagan's "pay-as-you-go" funding approach for federal agencies. From the FCC's standpoint, the VE system took nearly all the expense of the testing system away from the FCC. Exams would be conducted by volunteer teams organized and supervised by FCC-approved Volunteer Examiner Coordinators (VECs). The examinations to be used would also be developed by the coordinators, subject to approval by the FCC. The FCC's expense was reduced to the very minimal effort of supervising the VECs. The Goldwater bill also extended the normal license term to ten years and made all licenses renewable (prior to that time, most licenses were for five year terms, and Novice licenses were nonrenewable), which also reduced FCC expense (the longer the term, the less paperwork the FCC has to process). As an extra bonus, the testing process got a lot easier for most hams; now exams would be held at times and places that were convenient for the VE teams and the examinees, not at times that were consistent with govenrment business hours. Our team holds ten regular sessions a year, on the first Friday of each month (except July and January) at 7:30pm, one additional session at the end of our annual training classes, and special sessions as the need arises.

Each volunteer examiner team consists of at least three Volunteer Examiners (VEs) each accredited by a Volunteer Examiner Coordinator (VEC). To be a volunteer examiner, an individual must be a currently licensed amateur radio operator at least 18 years of age whose license has never been suspended or revoked. An individual may be accredited by more than one VEC (many VEs are accredited by multiple VECs, although personally I'm only accredited with the ARRL/VEC), but all VEs at a given session must be accredited by the coordinator that is sponsoring that session. There is no requirement that VEs be citizens, but non-citizen amateurs do have to hold a US-granted license; it's not enough to be permitted to operate as an alien amateur radio operator under a reciprocity agreement.

The VEs administering an exam must be of a license class greater than the license that the exam being administered would qualify the candidate for, except that an Extra VE may administer any element (since there is no license class greater than Extra). In specific, the three examiners giving an exam for Element 2, the test which qualifies one for the Technician license, must all be of General class or higher. Under the current system there is no class below Technician for which a new license can be earned, and so there is no point in having Technician VEs. Before the elimination of the Novice license, it was possible to get the Novice license, and only the Novice license, at a VE session attended by only two Technician-class or higher VEs, but those days are behind us now. Some (but not all) VECs will only accredit Extras; in any case, most VEs are Extras.

One of the really nice features of the VE system is that a VE team can hold a testing session at literally any place or time as long as there are three VEs available to be in the same place at the same time, all accredited by the same VEC (and not a "close relative" of the examinee, and, yes, the FCC has a precise definition of "close relative"). This means, for example, that we can administer a test in the home of someone who is unable to travel due to disability; this goes a long way toward making the hobby accessible to people with disabilities. It also means that a session can be held at a convention or other event where interest is discovered, even on relatively short notice.

While the questions and answers used on the exams are provided by the NCVEC, the final determination of the correctness of any examinee's answer rests with the VEs. There was a question on the old Extra pool (removed in the 2008 revision) that had the same answer for both answers A and C in the question bank, with only A being considered correct, although obviously C is as well. The VE team would be within its discretion to consider C correct as well. In the event this discretion is abused (or for any other reason that the FCC finds reasonable), the FCC may order any licensee to be retested either by the FCC itself or by such VEs as the FCC may direct; failure to comply with such an order will result in the cancellation of the license. (This power has not often been used.)

The test to become a VE (at least as managed by the ARRL/VEC) is not very difficult, and it's not uncommon for Extras to decide to take this "next step" in the service to the hobby. The club I'm a member of (the DuPage Amateur Radio Club) has a great supply of VEs, and we routinely have more VEs at our sessions than we do examinees. However, I've heard that in other parts of the land, VEs can be hard to find. For those of you who have reached the "pinnacle" of Extra, why not take the time to fill out a relatively simple form, answer a few questions, and earn your very own VE badge? (You don't have to be a ARRL member, and the rules regulating VECs prohibit the fees collected by the ARRL/VEC from flowing back to the ARRL general fund, so if you should happen to not support the ARRL, understand that you aren't funding them by participating in the ARRL/VEC or by taking an ARRL/VEC coordinated exam.)

This post has been brought to you by pool questions T1A04, T1A06, T1D06, G1D07, G1D10, G1D11, G1D12, G1D13, E1E04, E1E05, E1E06, E1E07, E1E12, E1E17, and E1E20.

The Incentive Licensing System

2009-10-20T23:56:00.000-05:00

In the United States, at least, the amateur licensing system has always incorporated multiple classes of license. A full history of the system is beyond the scope of what I want to write for this article. For most of the last few decades the FCC's approach has been to use increased privileges as an "incentive" to upgrade, giving rise to the name "incentive licensing system".

Prior to April 15, 2000, there were six license classes that could be earned in the incentive licensing system. These were Novice, Technician, Technician Plus, General, Advanced, and Extra. It's not entirely possible to arrange these in terms of increasing privileges, because Novice and Technician (both considered "entry level" licenses) had different, incompatible privileges: Novices had limited HF privileges but relatively few VHF and UHF privileges, while Technicians had no HF privileges at all but full privileges above 50 MHz. The Technician Plus license had exactly the combination of the Novice and Technician licenses and was earned either by upgrading from Novice or upgrading from Technician. The General, Advanced, and Extra licenses all granted steadily increasing privileges. The big step then, as now, was from the introductory licenses of Novice, Technician, and Technician Plus to the broader General license, which gave access to almost all of HF; the only operating privileges gained with the Advanced and Extra licenses were access to small slivers of reserved spectrum in certain HF bands. (There are other privileges gained by virtue of holding Advanced or Extra licenses, but those relate mainly to reciprocal operation, the Volunteer Examiner system, and access to shorter call signs, all topics that I will cover in later posts.)

In 2000, the FCC semi-eliminated the Novice and Advanced licenses. Existing holders of these licenses would retain their licenses and the privileges associated therewith, but no new licenses would be granted in these classes. That reduced the number of license classes that one could obtain to three (or four if you count the "Technician Plus" license endorsement). The 2000 revision also eliminated all Morse code tests other than the 5 word per minute test, which remained required for all licenses except Technician.

Subsequently, in 2007, the FCC eliminated the Morse Code requirement from the licensing system. This effectively upgraded all Technicians to the "Technician Plus" license (thereby granting all Technicians at least limited access to HF) and finally made the license privilege grants strictly increasing with increasing license class. As a result, there are only three licenses that one can earn at this time: the entry-level Technician license (with full VHF+ privileges, and very limited HF privileges), the mainline General license (with the same VHF+ privileges as Technicians and a wide variety of HF privileges excluding only a few slivers of spectrum in four of the contesting bands), and the "elite" Amateur Extra license (with the widest range of privileges available to any amateur).

The historical status of the Novice license still shows up in a few other places; there are a few privileges that are granted to all amateurs holding a "Technician-class or higher" license, which seems strange in the current context but is necessary because there's still some 10,000 Novice licensees hanging around. The main privileges granted to Technicians but withheld from Novices, other than full and unrestricted use of the VHF and higher bands, are the privileges of operating the various "special operation" stations (auxiliary, beacon, and repeater). Novices are permitted to operate stations in the amateur satellite service (space, ground, or telecommand), but the very limited VHF privileges of Novices make it difficult to actually do this. For example, a Novice would not be able to communicate with the ISS using amateur radio (under his own privileges) because a Novice has no privileges on 2 meters or 70 centimeters. (By the way, this is something I learned writing this post. I learned, while studying for my exams, that one had to be at least a Technician to work ISS, but didn't learn the reason at the time. I had mistakenly thought that Novices couldn't operate stations in the amateur satellite service. That would be wrong; I had the right answer but for the wrong reason. Novices may indeed operate stations in the amateur satellite services, but are very limited in doing so by their really rather limited frequency privileges.)

There has been a great deal of criticism of the FCC's approach to licensing. For example, Technicians are authorized 1500 watts on just about all amateur bands above 50 MHz, including the microwave bands, and so a Technician could legally build a "catcooker" by constructing a 1500 watt microwave transmitter. While this is true, it doesn't appear to be a serious problem; there is not a rash of cats being inadvertently cooked by newly-minted amateur licensees running around with ill-considered microwave transmitters. Another common complaint is that the step from General to Extra is much larger than the step from Technician to General, but the privileges gained from Technician to General are much larger than the gain from General to Extra. This is true. There's not much of an response to be had to this, either; unless you're a contester, the Extra license doesn't give you a whole lot beyond the General. Still, enough people go for the Extra (myself included), so there must be something to it.

Many countries restrict power levels, modes of operation, and choice of equipment for introductory licensees. For example, Basic licensees in Canada are limited to (in general) one-quarter the power of Advanced licensees, and in both the UK and Australia Foundation licensees are restricted to using transmitters that have been commercially manufactured (as opposed to homebrewed). While similar proposals have been made from time to time in the United States, none of them has caught root. This is, perhaps, a consequence of the Technician license having been originally intended for experimenters who would have been expected to build their own equipment.

I'm personally not that thrilled with the incentive licensing system as it stands now, but at the same time I've yet to see a proposal to replace it with anything that would be better. There's not enough evidence that it's currently broken, so I supose it's not really worth fixing.

This post has been brought to you by pool questions T1A03, T2C03, and T7B04.

Why do we have amateur radio?

2009-10-19T10:24:00.002-05:00

The reasons why people become hams are myriad, and a full understanding of that is probably beyond the scope of this post; if you want to read more on this, perhaps see this older post of mine. But that's not what I'm going to talk about here. Rather, I'm going to talk about why the government continues to let us play with radios, when countless other entities are continuously clamoring for more spectrum.

The FCC recognizes five purposes to the amateur radio service (and the NCVEC expects you to know at least three of them for the Technician test):

Recognition and enhancement of the value of the amateur service to the public as a voluntary noncommercial communication service, particularly with respect to providing emergency communications.
Continuation and extension of the amateur's proven ability to contribute to the advancement of the radio art.
Encouragement and improvement of the amateur service through rules which provide for advancing skills in both the communications and technical phases of the art.
Expansion of the existing reservoir within the amateur radio service of trained operators, technicians, and electronics experts.
Continuation and extension of the amateur's unique ability to enhance international goodwill.

It's occasionally difficult to explain how the routine activities of most hams fit into any of these five categories. VHF repeater ragchewing, for example, doesn't seem to fit well into any of these; at best it's got something to with the reservoir of trained operators, but if you've ever listened to a group of VHF ragchewers, you'd be hard-pressed to consider them "trained operators". And one thing amateur radio is absolutely not intended to be is a routine substitute for cell phones or email or any other such service. Amateur radio services are not intended to be used for passing messages for the general public, except when no other alternatives are available; this is why ARES and other emergency communications groups often use the motto "When all else fails..."

Far too often hams seem to forget that their license is granted to them by the government on the condition that they use it, at least some of the time, in the furtherance of these purposes; at the very least, we should not act contrary to these purposes in our amateur radio activities. If for no other reason than that if we don't at least make an effort to reflect the government's interests in amateur radio, it'll get harder and harder to justify our special privileges with them.

This post has been brought to you by pool questions T1A02 and T1A08.

How long does it take to get an amateur radio license?

2009-10-18T15:14:00.001-05:00

This question is one that we get asked quite frequently at VE sessions, typically by people who've just successfully completed their examination for Element 2, thereby earning their first amateur radio license. (And actually in those cases it's "How long before I get my license", but anyway.) Most of them are pleasantly surprised to find out that the answer (for us, at least) is "typically about five or six days". We're an ARRL/VEC VE team, so we submit our results back to Newington by priority mail, which tends to result in them hitting the FCC database (ULS) about three business days later, and as we test on Friday evening that usually means the resulting licenses clear ULS on Wednesday or Thursday. Some VE teams, notably Laurel VEC, submit results electronically, which results in new licenses making it onto ULS sometimes within 24 hours. How's that for instant gratification?

Of course, this question comes up because (as anyone who has recently studied for the Technician license knows), one is not permitted to go on the air until one's license actually appears in the "ULS consolidated licensee database" (unless one qualifies for a reciprocal operating grant as an alien); until this happens, one is not technically an "amateur radio operator". However, it's rare indeed that the study guides that most people use to prepare for the exams tell them how long it takes for this to happen.

This is another area where US hams have it good. Very few countries have turnaround this quick; more typical waits range from a week or so (most of Europe) to months or even years. I know a guy in India who tested nine months ago who has yet to receive his license; he didn't even find out that he passed until two months after the test. We tell you if you passed or not immediately (the FCC regs on the VE program mandate this).

I haven't talked about how long it takes to learn what you need to know to get the license. That's because that's really a function of the student. Some people can learn this stuff in a few hours; others will take a bit longer. There's a group that's been doing one-day classes for years with a pretty high success rate. I personally spent about a month in preparation for the tests, but I took all three elements at one time and I'd say that most of my study time was spent on the material for the (much harder) Element 4 test for the Extra license.

This post has been brought to you by pool questions T1A01, T1C01, and T1D05.

Do I have to coordinate my repeater?

2009-10-17T13:53:00.001-05:00

The title of this post was a search that hit my blog recently. Now, in order to discuss the topic, I'm going to make a couple of assumptions: first, that the individual in question is interested in American practice (since the IP address in question geolocates to Alabama, I'd say that's a safe bet), and that the repeater in question is an amateur repeater, rather than a commercial one. (I'll touch on the situations in the commercial services, and in other countries, at the end of the post).

My immediate reaction to the question is, of course, "If you don't know the answer to that question, you shouldn't be running a repeater." That is, I suppose, a bit harsh of me. Part 97 is pretty unclear about coordination. Frequency coordinators are only mentioned twice in Part 97, once in the definitions, in §97.3(a)(22), and once in §97.205, which specifies the special rules that apply to the operation of repeaters. All §205(c) says is that if one repeater interferes with another repeater, the operators of both stations are primarily and equally responsible for resolving the interference, unless one of them is coordinated and the other is not, in which case the uncoordinated station's operator is primarily responsible for resolving the interference. That doesn't equate to mandating coordination. In fact, Part 97 nowhere mandates coordination, and so that's the answer to the question: assuming you're in the United States and you're talking about an amateur radio repeater, you do not have to coordinate your repeater. Unless you're in an area with lots of repeaters, there's a good chance that not coordinating your repeater will turn out to be no big deal; just pick a frequency nobody is using for anything at the moment and have fun.

Of course, if there are a lot of repeaters in your area there might not be any frequencies that nobody is using. And even if there aren't, if the local repeater coordinator council is run by a bunch of annoying busybodies (as many of them are), they might arrange for your uncoordinated repeater to "interfere" with a coordinated repeater just to teach you a lesson. People are, after all, people, and politics are often at their worst when the stakes are the lowest. Not coordinating a repeater that's intended to serve a large area or large number of amateurs is probably not a good idea, for a lot of different reasons. But if you're just putting up a small repeater to cover you and a few guys down the street, it's probably not worth the hassle. And many coordination bodies have gotten way too big for their britches; I think some of them miss the days when coordination was mandatory.

Of course, repeatars in the commercial services have to be coordinated, but then again virtually all uses of commercial frequencies have to be preapproved by a frequency coordinator of some sort. And the "permissive coordination" practice that US amateurs enjoy is pretty unusual; most other countries have some form of mandatory coordination, either through their regulatory agency directly or through a coordinating body assigned by the regulator. American hams really have it pretty easy, in comparison.

Wiktionary and the USPTO

2009-10-15T22:33:00.001-05:00

A few months back (my web reading backlog is ginormous, really) I ran across a mention that the USPTO had denied a trademark application for a Twitter-related trademark on the basis that "tweet" is "merely-descriptive" on the basis of a Wiktionary entry defining "tweet". Twitter's own application for "tweet" was (as of July) still outstanding. Now, wouldn't it be funny if one of Twitter's own marketers was behind the editing of that Wiktionary article?

Of course, brand creators always walk a fine line in trademark, lest their descriptive term become "generic". I still think it's very touchy for the USPTO to be using Wiktionary as evidence of "mere descriptiveness", however, especially since Wiktionary is just as much at risk to being edited by anyone at all as Wikipedia is, a situation which has led to Wikipedia being essentially banned from the federal courts. Not to menion the New Jersey court that held that Wikipedia's volatile nature means it doesn't meet the evidentiary standard for judicially noticable facts. I don't see how the trademark examination process is so distinguishable that these precedents should not apply there as well.

The Guardian gets it half right

2009-09-02T16:34:00.001-05:00

A recent article in the Guardian, reacting to the news that the English Wikipedia is about to hit 3 million articles, and the news that Wikipedia's growth appears to have fallen out of the logistic phase, made the mistake of, for all intents and purposes, listening to Aaron Swartz. The first part of their piece, covering the statistical findings from PARC regarding Wikipedia's growth dropoff and increasingly hostile environment for casual editors, is all spot on, but the second part, in which they blather on about inclusionism and deletionism being a "significant battle" in Wikipedia, is significantly misinformed. I suppose that's what they get for talking to Aaron, who has never been a significant player in Wikipedia's community. I suppose they picked him as their "random Wikipedian" because he's something of a internet celebrity for reasons entirely unrelated to Wikipedia, and because he's got an ego larger than Montana.

The "struggle" between "inclusionists" and "deletionists" pales to irrelevance in comparison to the more serious struggles among all the pitched camps of ideologues in Wikipedia. Both "inclusionist" and "deletionist" are reasonable philosophical attitudes that one can take toward the activity of editing an encyclopedia. However, the ideologues do not fall reliably into either category, because they each individually favor including only that content that furthers their respective personal agendas, and favor deleting content that opposes those agendas. The friction in Wikipedia's community comes largely from these ideological battles (which can be on nearly any topic, although perennial ones are the Middle East, animal rights, and Northern Ireland), not from any dispute over philosophical attitudes related to encyclopedic worth. Wikipedia has never developed any meaningful way to resolve content disputes, so these matters usually end up being settled with one side goading the other into breaking enough of Wikipedia's polymorphic conduct rules badly enough to get themselves banned.

Unfortunately, there's no good statistics on how biased Wikipedia content is. It's not easy to measure bias. It's not even easy to define bias in any objective way. At least the inclusionist/deletionist axis is simple to define and one can identify individual Wikipedians on that axis by examining their deletion votes (which, while tedious to do, presents no serious evaluatory challenge). Given that, I suppose it's excusable that the Guardian fell for it when Aaron told them that this was actually an important division within Wikipedia and that the current factionalism of its community (which is very real) is somehow derived from that. To be honest, Wikipedia would be a much better place if the inclusion question represented the most serious division within its community.

How The ITU Screwed Over Fiji and Swaziland

2009-08-25T17:04:00.001-05:00

In the past I've written a bit about how amateur radio call signs (and call signs generally) are formed. Basically speaking, the ITU has allocated various prefixes to various nations, with some nations getting a lot (e.g. the US, which has all of W, N, and K, and AA through AL), and others just a few (such as Tonga, which just gets A3).

But there's two countries who really get the short end of the stick on this issue: Fiji and Swaziland, who have to share the 3D prefix between them. Technically, Swaziland has 3DA through 3DM and Fiji has 3DN through 3DZ. However, amateur radio call sign prefixes, according to the ITU's own standards, are at most two characters; a call sign that begins "3DA" is not compliant with § 30 of the ITU's standards. This puts Fiji and Swaziland into the difficult position of being unable to issue conformant callsigns to amateurs within their jurisdiction.

In practice, Fiji issues call signs with the prefix 3D2, while Swaziland has issued call signs prefixed 3D6 and (nonconformantly) 3DA0. Neither country has very many hams, but both are occasionally the target of DXpeditions, especially Fiji (due to being an island).

Still, it amuses me that Fiji and Swaziland have to share a prefix, while both the ICAO and the World Meterological Organization get whole prefixes to themselves (4Y and C7, respectively) despite not even being countries. I suppose they must have been late to acceed to the ITU treaty or something, to be singled out for such inauspicious treatment.

Are crowds really all that wise?

2009-08-25T09:59:00.005-05:00

So I've been thinking a bit about why Wikipedia actually seems less trustworthy on so many issues than just picking random websites with a Google Search. And last night, it came to me, while arguing with someone on IRC over why I don't trust Wikipedia for most topics.

Most websites put up by most people are put up by people who are trying to tell you the truth, at least as they believe it to be. That is, they're not deliberately trying to lie to you. Now, there are some sites that are actual hoaxes, but not many, and they're often obvious, but not always. And of course there are sites that are put up by honestly misguided fools, but these are also often obvious, but not always. And there are outright propaganda sites that are deliberately lying to you (to some extent or another), and these too are often obvious, but not always.

Wikipedia's content, like the rest of the web, is no different in general character: most of its content is contributed by people who believe it to be true (although quite often they're wrong), but mixed in with that is some quantity of deliberately false information, mainly hoaxes and propaganda. It's my argument that Wikipedia is a magnet for hoaxes and propaganda, and thus that Wikipedia quite likely contains more hoax and propaganda content than the Web on average, and that Wikipedia's format makes it harder to spot hoax and propaganda content.

Suppose, for a moment, that you're someone interested in spreading hoax or propaganda content on the web. Now, you could just create a website and put your content on it. But that approach isn't going to be all that effective by itself: nobody is going to have much of an incentive to go to your website. Now, you could launch your site and then run an aggressive marketing campaign to try to draw people to your site, but even then you have the problem that your hoax or propaganda content is going to be in a context that isn't necessarily going to convince people to believe it. You might get lots of visitors (which, if you're just after pageviews, may be all you want), but you aren't likely to get many believers.

A more effective way to convince people to fall for your hoax or propaganda is to try to insert it into Wikipedia. People are already going to Wikipedia, so you don't have to drive traffic there, so no marketing campaign required. And people are inclined to believe Wikipedia because it presents itself as an encyclopedia, and people (stupidly) assume that that means some reasonable effort to maintain accuracy is made. Of course, you have to keep Wikipedia's content police from removing your hoax or propaganda, but experience has shown that this actually isn't that hard to do, especially if you can find some difficult-to-check citations to back up your claims (few Wikipedians will bother to check off-web or pay-for-view citations, for example). Unless the place where you choose to insert your hoax or propaganda material is already being closely watched by a powerful Wikipedian, odds are your content will stand for quite some time. And if you take the time to inveigle yourself into Wikipedia's "community" first (which isn't really all that hard), it might last even longer.

The difference between a random site on the Internet, and Wikipedia, however, is that for content on a random site you can evaluate that content in the context of the rest of the site; that may tend to give you an idea as to whether you can trust the author(s) of that site for reliability. Wikipedia makes this harder to do, because articles may have dozens of authors and examining each of the contributions of an individual author can be extremely timeconsuming and tedious. Most people coming across a website asserting something vaguely incredible where there was just the one page on that site and no other context in which to evaluate it, would probably reject the assertion. But come across the same assertion on Wikipedia, and most people are going to be more willing to accept it, even if that assertion is that author's only contribution to WIkipedia, because of Wikipedia's "cachet" as an encyclopedia and because of the difficulty in evaluating the trustworthiness of individual article authors in Wikipedia's context.

So, it seems to me that if your motivation for publishing on the Internet is to change people's minds on some issue, there's a real incentive for you to do so by trying to edit your viewpoint into Wikipedia instead of publishing on your own site. I'm sure I'm not the only person to think of this, and so we must assume that this is actively going on at Wikipedia, and that therefore Wikipedia content is at least as likely to contain hoaxes and propaganda as the rest of the Internet. If anything, Wikipedia should contain more such content, because it is an "attractive nuisance" in that regard: the relative ease of inserting such content into Wikipedia and getting it to stick relative to creating one's own website makes the Wikipedia option more practical, and so Wikipedia should actually be less reliable than the Internet as a whole.

Wikipedia is a great source for popular culture trivia, but it falls down on topics that involve any degree of controversy (because of the ease of using the platform for advocacy) or that require advance knowledge to effectively evaluate (because Wikipedia's content police, who are generally mostly ignorant of most issues, cannot evaluate the merits of individual contributions). Combine that with the attractive nuisance aspect for hoaxers, propagandists, and revenge-seekers, and it's no small wonder that the discerning choice when searching for information on the Internet is "-site:wikipedia.org".

"Unlimited" means "limited" at Skype

2009-07-29T14:04:00.002-05:00

Some of the local hams have been talking about Skype a lot lately, presumably because someone introduced it to them and it is kinda neat at first and it is free in its basic incarnation. Now I used to use Skype because of a few Wikipedia-related things that made use of it, but I haven't for quite a while now.

On their front page Skype is advertising, in big letters, that you get "unlimited" calls to cell phones, mobiles, and land lines with its subscription service. But the careful reader that I am notices that there's a suspicious looking asterisk on "unlimited" and notes that there's a Marketing Qualification on that "unlimited": a "fair use policy" applies to your "unlimited use", and in fact you're only allowed 10,000 minutes a month, six hours a day, and not more than 50 distinct numbers a day.

To be fair, there are only about 40,000 minutes in a month, so in order to exceed this "fair use policy" you'd have to be on the phone six hours a day, every day, but still, that's a limit. "Unlimited" means "no limits", not "a high limit that you're unlikely to reach".

What Skype doesn't say explicitly, but is clearly intending to do, is prohibit the use of their service for commercial purposes, more specifically for telemarketing. Which is reasonable. I'm just peeved at the idea that "unlimited" has defined, fixed limits.

Still, it beats Comcast's notion of "unlimited", which is "unlimited unless we decide you're using too much according to no defined standard, in which case we'll suspend your account without warning". At least Skype sets forth a standard and tells you the consequences for exceeding them up front.

Closed repeaters: to ban or not to ban

2009-07-29T00:20:00.003-05:00

This morning (well, by now yesterday morning), while cruising the Internet (as I am wont to do in the mornings), I noticed a link to a site called the Rain Report at which, according to Bob, had something about a petition to outlaw "closed repeaters". Getting there I didn't find a whole lot of detail except for an audio file which I was not about to take the time to listen to, and a call sign: K3BEQ, who turns out to be Murray Green. A bit more digging found not the current petition, but instead an older petition from K3BEQ on a completely unrelated topic (extending the time between required identifications to thirty minutes, which was denied by the FCC) as well as a much older proposal by WB4RTP which does have something to do with closed repeaters, and an current online petition also seeking a change in the regulations related to closed repeaters.

None of the sites I found, though, detailed Mr. Green's specific proposal, nor could I find it at the FCC or at the GPO site. Fortunately, I lucked out and found an old ARRL news article that gave Mr. Green's email address. A quick email to him and he was gracious enough to send me a copy of his petition. Calling it a "ban on closed repeaters" is perhaps a bit overstating it, but let's set some background first.

I've written a bit on this before, arguing (somewhat in passing) that closed repeaters should be refused coordination. A "closed repeater" is a repeater, set up by some group, the use of which is only available to members of that group (and invited guests), and not available for the general use of any amateur. This may be enforced by the use of selective calling methods (such as CTCSS or MDC) or merely be a matter of custom enforced by social controls, and when necessary legal threats. The principle behind this is that the repeater is the property of its owner, and its owner has the legal right to control who can use it and how, pretty much without limitation.

Most repeaters are available for the use of any amateur; if there is a CTCSS tone in use (as there often is to mitigate interference and reduce inadvertent retransmissions), it is published and widely known, and any amateur with the technical ability to transmit on the repeater's input is welcome to use the repeater as long as they do so "in accordance with good engineering and good amateur practice". However, nonsubscribing amateurs are typically not permitted to use a closed repeater, and may face the risk of civil lawsuits, criminal prosecution, and suspension or termination of their licenses, if they should use a closed repeater without permission. Closed repeaters are relatively rare in most parts of the country, but in some of the more densely populated areas (Southern California and the Potomac River Valley are two that come to mind) there are quite a lot of them; so many, in fact, that it may not be possible to get a coordinated frequency pair for a new repeater in any of the commonly used repeater bands. There's a few of them here in the Chicago area.

Mr. Green clearly believes that the situation has gone too far. (It should be noted that he lives in the Potomac River Valley, one of the most ham-dense areas of the country.) His petition asks the FCC to amend the regulations to remove the language in §205(e) to remove the language that explicitly permits a repeater operator to restrict access to the repeater and replace it with language that would prohibit anyone from "limiting the use of frequencies used by repeaters". His main argument is that the current rule is inconsistent with §101(b) (which states that no frequency will be assigned to the exclusive use of any station), and that it also results in poor utilization of amateur radio frequencies. In further support of his position, he argues that closed repeaters are intimidating to newly licensed amateurs, and may create a negative atmosphere within the community and harm the public perception of amateur radio. Unfortunately for his proposal, he provides no evidence in support of any of these claims.

Now, I'm a bit sympathetic to K3BEQ's position here, but I think there's no chance of the FCC adopting this proposal as it stands. While Murray does at least set forth an argument why the current regime creates harm, he provides no evidence of that harm, and my experience is that the FCC will generally not act on the assertion of harm without evidence to back it up. Also, he doesn't provide any clear explanation how his proposed change mitigates that harm. In addition, the language of his proposed replacement for the final sentence of §205(e), "Because repeaters and their coordinated frequencies are inseparable, and to make more effective use of amateur radio service repeater frequencies, limiting the use of frequencies used by repeaters, directly or indirectly is prohibited, except where a user blatantly violates the Commission Rules," goes much further than required to remedy the alleged harm. And, finally, there's the problem of the claim that "repeaters and their coordinated frequencies are inseparable", which is neither supported by evidence nor in fact even true.

If I were to contemplate sending a petition to the FCC on this issue, here's how I'd go about it. First, I'd get the coordination rosters for some of the more densely populated areas, such as southern California, DC metro, New York, Boston. Using those rosters, document that most or all of the available frequencies for repeaters within the repeater plans in use in those areas are currently allocated, breaking down what percentage of those allocations are to closed repeaters. Also document, by affadavit if by no other means, that many of these repeaters are silent most of the time (many of them in reality are barely more than "talking clocks"). Document, if possible, how long it takes for a new coordinated pair to become available in one of these regions. This would demonstrate a particular harm that the current system is creating, that being frequency exhaustion (a problem the FCC completely understands, since it is struggling with it constantly in the other services it regulates). Finally, document (by anecdote if by no other means) how closed repeaters conflict with the mission of the amateur radio service as set forth in §1; I know of at least one incident where a closed repeater's configuration prevented, at least for a time, the effective provision of public service communications (during a severe weather event) because of the technical measures used to restrict access to the repeater.

If the evidence thus collected does in fact show (as I expect it would) that closed repeaters are strangling frequency plans in at least some areas, preventing willing amateurs from setting up new open repeaters, and hampering the provision of public service and emergency communications, then the next step is to come up with a solution that would tend to mitigate these problems. The problem with K3BEQ's solution is that it doesn't reduce the number of "talking clock" machines taking up spectrum without actually utilizing it; it just means these people can't complain to the FCC when people use their machines (which would be a plus to the FCC, to be certain). If the data does tend to suggest that closed repeaters are more likely to be underutilized, then an argument could be made for altering the rules to prohibit a repeater station from enjoying the protection from interference granted by §205(c) unless that repeater is operated so that it is available for the use of any amateur whose is himself not violating the Commission's rules. That would then give frequency coordinators a reason to be less generous in coordinating, or to deny coordination entirely, to closed repeaters. You could still run one, but you'd be running barefoot.

Of course, another option is to petition one's local coordinating body to alter its rules so as to not coordinate closed repeaters, or to give preference to open repeaters over closed repeaters when granting coordinations (so that, e.g. a closed repeater might lose its coordination if an open repeater comes along and no other frequencies are available). However, most repeater coordinating bodies are going to be unlikely to agree to such a change, because the voting membership of these bodies is the operators of coordinated repeaters, including closed repeaters. In an area where closed repeaters dominate, such a proposal would be unlikely to gain a majority, for obvious reasons. Getting action from the FCC, as difficult and unlikely as that is, is probably easier than convincing some of the old boy clubs that are coordinating councils to change their minds on this issue.

The FCC denies virtually all petitions for rulemaking that come from amateurs, and I don't expect this one will be any different. It's still a pretty important issue, and I think one that is ripe for some attention, especially with the spectrum audit that is currently underway. We've got a large chunk of spectrum in 70 centimeters especially and there's plenty of people who'd love to grab a hunk of it.

You know you're a ham when you...

2009-07-27T09:49:00.004-05:00

The other day I got a referral to my blog on the search "You know you're a ham if". This piqued my curiosity, so I asked my Twitter followers to complete the sentence "You know you're a ham when you...". I got quite a few responses; here's the best, for your satisfaction. (Some have been edited to undo IM-speak imposed by Twitter's 140 character limit.)

Obsessive operation:

"... stand in your driveway with two HT's watching an approching thunderstorm giving continuous updates on the radio" Dave Hoffman (via FriendFeed)
"... see a meteor fall and wonder who you could've worked on meteor scatter" k4hsm
"... participating in SkyWarn is more important than your brother's wedding." karmagurl, channeling her husband
"... go to bed with your wife and an HT in case someone calls you on the local repeater" AF3LMike
"... can predict the weather better then the weatherman by noises on the bands" N3PRO
"... look forward to new solar activity cycle instead of fearing it" ttanilsoo

Too much equipment:

"... have an aerial farm covered in tinsel at christmas" ai4ri
"... other people are no longer surprised when you pull an oscilloscope from the trunk of your car." N9VLS
"... get excited that Radio Shack starts carrying a new style connector/adapter that you don't have already" charlieray
"... there's not enough room in the passenger seat of the truck for you; ham equip. takes it all up!" karmagurl

Obsessive jargon:

"... end your work emails w/ 73s and reference your RL-in-person convos as QSOs" enjaysauce
"... tell your friend there's QSB when a cell phone is cutting out" thebuca
"... start giving RST reports over the telephone" AF3LMike

Just obsessed:

"... see a radio station / TV tower and wonder how a repeater would work from up there" k4hsm
"... are walking in the city and stare at the antennas on the rooftops of the buildings and analyze their type" ttanilsoo
"... know 23cm means more than just a really good date." Ben Hallert (via Facebook)
"... named your kid Yagi" enjaysauce

Morse code pervades all

"... tap out hi on your car horn to another ham" AF3LMike
"-.-- --- ..- / - .... .. -. -.- / .. -. / -- --- .-. ... ." gwbrown1

And for the more culinary crowd:

"... continually find yourself covered with mustard" strategy_samba
"... find yourself between a bit of bread and some cheese" wwward

Enjoy.

Unexpected associations

2009-07-25T14:41:00.002-05:00

The other day I dropped something off my desk, which is something that happens from time to time. It rolled behind me, and my first thought was "I should make sure that didn't fall down into the heating vent." This was immediately followed by the thought, "What heating vent?", which left me so confused that I didn't actually pick up whatever it was that fell.

Our current house has hot water baseboard heat. There are no heating vents, just baseboard heating elements around the exterior walls of each room. The fact that this house has baseboard heat is one of the reasons we bought it: I think hot water baseboard heat is an entirely superior heating methodology, compared to central forced air heat. We've lived here now over two years, so you'd think I'd be used to it by now. So where'd the idea of something falling into the vent come from, you ask?

Simple. Behind me at my desk is a buffet cabinet that, at our old house, used to sit over the main return vent for the first floor. The grate over that vent was less than fully adequate, and things did routinely fall through it and into the vent. We lived there for six years, and I guess on some level my mind associates that buffet cabinet with the concept of a heating vent.

It took me a while to figure out where I was getting such a bizarre thought from. It's strange how the mind works. (Or maybe it's just me.)

Weather radios

2009-07-18T23:55:00.003-05:00

A friend recently sent a link to this desktop weather alert radio, which is manufactured by a company called Reecom. Reading through the manual, it has a few features that make it slightly nicer than the Midland WR-300 I'm using now, the most significant of which to me are the ability for it to turn off at the end of the alert message (the Midland continues to babble at you until you walk over and whack the 'silence' button, which is somewhat annoying) and the ability to select different audible alerts for different messages. I'm not immediately in the market for another weather radio (for no other reason than that my virtually nonexistent income at the moment doesn't support nondiscretionary spending), but this looks like it might be a good additional radio (I've wanted a second one so that the alerts can be heard through the entire house instead of just in the back, which is the effect with the current radio in its current location).

We originally got this radio because we realized that we cannot hear the alert sirens inside the house, and given that we rarely listen to broadcast radio and watch nearly all of our television via TiVo did not have any means to receive weather alerts in real time. I'd rather not find out about a tornado when it rips the roof off the house.

I'm also interested in options that will capture the message off the air and make it available to a computer. The Reecom radio (and the WR-300) can be used to detect that an alert is active, but without hacking the radio I don't know how to get the details of the alert (e.g. type of alert, duration, affected areas) into the computer. I could, of course, obtain this information from the NWS's website, but that's not much help if the network is down. I assume that there's a specification somewhere for decoding the EAS data bursts, and that someone has written code for this. Just haven't found it yet. Not to mention it'd be nice if I didn't have to dedicate a whole soundcard to that (that is, a hardware solution would be much nicer than a software one).

How Do Ten Meter Repeaters Work

2009-07-14T06:51:00.002-05:00

Here's another topic discovered from search engine referrals. I'm unclear whether the searcher is looking for information on how repeaters of any sort work, or the specific differences between ten meter repeaters and other types of repeater, so I'll cover both topics.

Just about anyone who's been involved in amateur radio for any time at all will have encountered a repeater, and for many hams (especially those in the US with Technician licenses) repeater operations are the majority of their activity, so it's probably safe to say that repeaters are at least somewhat important to hams. (They're also important to other radio services, but I won't get in to that in this article.) Fundamentally, a repeater is an automatically controlled station that receives a signal and immediately retransmits that same signal back out. The idea behind this is to enable two stations, each of which has relatively limited power, and more significantly, relatively limited antenna systems, to communicate with one another by way of the repeater station, which will typically have more power and, more importantly, a much better antenna system (where "better" in this situation means "installed at greater altitude").

As an example, a typical VHF mobile installation will have an antenna with center of radiation at perhaps six or eight feet above ground level and a power level of perhaps 50 watts. Two stations thus equipped will be able to communicate directly with one another at a range of about ten miles in relatively flat terrain. However, if the repeater is equipped with a 100 watt transmitter and an antenna installed at 200 feet above ground, it should be in range to mobile stations equipped as above within about 25 miles. Furthermore, any two mobile stations within this range will be able to communicate with one another via the repeater. This represents about a six-fold increase in the ability to communicate.

So how does the repeater accomplish this? Fundamentally, a repeater is a receiver connected to a transmitter, combined with various control circuits (e.g. to prevent the repeater from transmitting when there's nothing to transmit, and for other purposes, some obligatory, others not). Now, one of the things that confused me when I first heard about repeaters back in the early 90s is how the repeater could receive a signal and transmit it back out on the same frequency without interfering with itself. The simple answer to this is that repeater don't do this: virtually all repeaters receive on a different frequency than they transmit. (There are some "repeaters" that operate "simplex" by delaying the transmission until the receiver message is complete, but that's technically not a repeater; the definition of a repeater requires simultaneous retransmission. And there are other repeaters that do operate on the same frequency in and out by using separate antennas at well-separated locations; we'll come back to that later.) Because the receive frequency is different from the transmit frequency, the transmitter doesn't interfere with the receiver and both function can proceed simultaneously. The difference between the receive frequency (or "input") and the transmit frequency or ("output") is called the "offset". There are customary offsets for most repeater operations, which vary by region (for various reason). In the United States, the customary offset for two meters is 600 kHz, and for ten meters it typically 100 kHz.

And here's another aspect of repeaters I failed to get at first: most repeaters use the same antenna for both receive and transmit. Of course, this raises another question: how do you put a 100 watt signal onto an antenna to be sent out, and at the same time pull in a signal measuring often in the nanowatts without the receiver being overwhelmed by the transmitter's raw power even if it is on a (somewhat) different frequency? That was another one I didn't really get until I started studying for my Extra. The answer is, of course, filtering, and the two main techniques for doing this are the duplexer and the circulator.

A duplexer is a set of filters that are designed to pass signals on one frequency with very little loss, while at the same time rejecting signals on another (often nearby) frequency with very high attenuation. In the repeater case, you want a filter on the receiver side that passes the input frequency with as little loss as possible, and attenuates the output frequency as much as possible, while on the transmit side you want the exact opposite. Because of the very tight tolerances required (only 600 kilohertz separation for two meters), these filters have to be very tight, too tight to be built out of ordinary discrete components like capacitors and inductors, so for virtually all repeaters these are resonant cavity filters. Resonant cavities provide much tighter pass bands and reject bands than any discrete circuit could. Even so, two, three, or even four filter pairs are typically required to provide sufficient isolation.

The other component that is useful in providing this isolation is a little piece of electronic voodoo called a circulator. A circulator is a device, typically constructed out of ferrite disks, with three ports that allows a signal to pass from port 1 to port 2, from port 2 to port 3, and from port 3 to port 1, but not in any of the reverse directions. To be honest I still don't fully understand how they work; it has something to do with the signals setting up a rotating magnetic field in the ferrite disks that cancels the reverse signals; at this point I'm happy to call them "electronic voodoo" and leave it at that. In any case, connecting the transmitter's output to port 1, the antenna to port 2, and the receiver's input to port 3 will also provide a significant chunk of the signal isolation required to protect the receiver from the transmitter. Many stations use some combination of duplexing filters and circulators to achieve the required isolation (which is a mininum of at least 60 decibels, more if possible) between transmit and receive.

This is really the hard part of the repeater from an RF standpoint. The rest of the repeater is just a more or less ordinary receiver tuned to the receive frequency, a more or less ordinary transmitter tuned to the transmit frequency, a little bit of audio-frequency circuitry to ensure that the transmitted signal is well-balanced, and some control circuitry to do things like transmit the station's callsign periodically, and turn the transmitter on and off as required. Of course, nearly endless features can be added to a repeater, but these are ancillary functions, not the core of the repeater functionality.

Now, on to the more specific question of ten meter repeaters. One of the characteristics of resonant filters is that one of the factors that determines their size is the wavelength of the pass frequency (the other, of course, is the filter sharpness, or Q, required). This is why two meter "cans" (as they're called, as they really do look like cans) are typically about the size of two paint cans stacked on top of one another, while cans for 70 centimeters are much smaller, about the size of a can of spray paint. This is because 70 cm is a third the wavelength of 2 meters, and in addition the customary offset in 70 cm is 5 megahertz, instead of the much smaller 600 kilohertz used in 2 meters. As a result, 70 cm machines (hams often refer to repeaters as "machines") can use physically much smaller cans. For ten meters, this goes the other way: ten meters has five times the wavelength of two meters, and the customary offset of only 100 kHz is even more demanding than the 600 kHz of two meters. A set of cans for ten meters capable of providing a reasonable degree of isolation would be at least the size of hot water heater tanks. If you read the article I linked above you'll note that the designer of those filters silver-plated the interior of the cavity filters to minimize loss; the cost of silver-plating that much surface would be quite substantial. Also, the very narrow offset would necessitate very finicky tuning.

Mainly because of this, it's more practical for 10 meter repeaters to use "diversity antennas" instead of filtering to achieve the necessary isolation. Separating the antennas by a mile or so will achieve as much signal isolation as would even the best possible filtering arrangement. In this approach, the receiver and the transmitter are at different locations, and the audio received at the receiver is conveyed to the transmitter's location either by a landline link (a physical hardline cable, a dedicated telephone circuit, or some other non-radio connection including possibly a VoIP circuit), or alternatively by transmitting the audio via a radio link operating in some other band. Typically these links are in the 70cm band and use very directional antennas that are carefully aimed at one another. (The same approach is use for multi-input repeater systems, but that's beyond the scope of this article.)

This same approach can be used in any band, but using diversity receive in any band other than ten meters (and perhaps six meters, where it is also occasionally seen) creates the problem that the coverage area where the repeater can be heard (which is based on transmitter location) may not correspond well to the area where the repeater can hear remote stations (which is based on receiver location). This is less of a problem for ten meters because ten meters has much broader propagation, due to skywave propagation modes including near-vertical incidence skywave (NVIS), and so the nonoverlap areas are likely to be smaller.

The "Syfy" Channel

2009-07-13T23:35:00.003-05:00

So, this past week the Sci Fi Channel recently changed its name to the just atrociously misspelled name of "Syfy" Channel. The ostensible reason? Apparently there's this nagging feeling at NBC Universal (who owns the Sci Fi Channel) that the name "Sci Fi" is holding them back, because that term is associated with nerds in basements and such not. The alternate spelling of "Syfy" is supposed to be more appealing to women.

Well, ok, whatever. They sound the same and for most people that's going to evoke the same feeling. Won't affect my tendency to watch their channel: I have almost no idea what channel anything in particular is on because I have been a TiVo user now for almost ten years. I just tell my TiVo what to record and it finds it and records it whatever channel it's on. (Besides, I watch maybe three hours of TV a week these days.)

That said, I miss the old Sci Fi channel, in the days before the new Battlestar Galactica (which I detest). They used to have much more science-fictiony content, but lately've they've definitely moved much closer to the mainstream perception of "sci-fi", such as the new BG. Frankly "Lost" is more science-fictiony than BG. So while I do occasionally watch some of their content, it's not often, and I don't seek it out.

Still, the real reason they changed their name? Branding. You can't trademark "sci fi" as a universal mark; it's a common phrase and trademark protection in common phrases is always limited in scope. But "Syfy" isn't a common phrase or term, and so the trademark they can get for that is exclusive; this gives them a much more powerful trademark and much broader branding opportunities. (This is why so many products have deliberately misspelled names.) That, dear friends, is the real reason for the name change.

The Philadelphia Experiment

2009-07-11T13:11:00.003-05:00

This is one of the odder things I've seen pop up on the Google Hot Searches list. The "Philadelphia Experiment" refers to supposed research done by the United States Navy in World War Two into the teleportation of warships, and more specifically the USS Eldridge, which, according to legend, was teleported from Philadelphia to Norfolk sometime during 1943. This apparently comes up often enough that the Naval Historical Center has a FAQ sheet on it.

Of course, conspiracy-minded individuals (of which I'm sure I have a few in my regular readership) will be inclined to find obvious proof in the Navy's denial of involvement. Can you imagine, though, being assigned to the Naval Historical Center and being given the assignment to research the records to provide proof that the Navy has never attempted to teleport a 1240 ton destroyer over 200 miles away by purportedly eldritch means? I wonder how many times the requesting officer had to explain to whoever he ordered to do this research just what it was he wanted.

(It also amuses me that the ship's name is so close to "eldritch", which any reader of Terry Pratchett will know actually means "oblong".)

The supposed incident was memorialized (if such is possible regarding an event which never occured) into an eponymous movie, which I have never seen (and not even heard of before yesterday). Apparently the movie and the underlying hoax are recurring elements in government conspiracy theories, especially those popular with ufologists.

Just had to share this, being one of the stranger things I've read about lately.

Change we don't quite know what to make of

2009-07-08T15:12:00.003-05:00

So the big question on everyone's mind right now (now that we're done with the Michael Jackson funeral, which occupied way too much of our collective attention, thank you very much) seems to be "Why did Sarah Palin resign as governor of Alaska?" It's not like she got caught having sex with a hot Argentinian (e.g. Sanford), or just generally being a prick (e.g. Blagojevich). Yeah, Palin's commitment to ethics does seem to have been a bit soft, but she's in a group of people that includes Rod Blagojevich, and in that company just about anything seems reasonable.

The title of this blog post was the caption of a political cartoon I saw today by Chip Bok. It really captured my bestartlement at hearing that she had resigned, and the complete lack of understanding that can be gleaned from her subsequent statements.

On a related note, Language Log has an interesting article today on the odd use of "I know that I know that I know" (or similar formations) that occurs in recent speeches by both Mark Sanford and Sarah Palin. Apparently this is yet another example of linguistic divergence within the American evangelical community; see also "dogwhistling", a common practice for Bush's speechwriters when he was President. To me it is somewhat scary that, to a large fraction of our country, ordinary sequences of words have special, nonobvious meanings. We risk becoming a country divided by a common language.

The Voice/Data Divide

2009-06-29T19:09:00.003-05:00

There's a discussion over on K3NG's blog over the legality of D*STAR, given that D*STAR uses AMBE, a proprietary vocoder the details of which are not publicly known. K3NG raised, reasonably, the FCC's prohibition (in §97.309) on the use of data encoding methods which are not publicly documented. I've previously mentioned this here in this blog, discussing APCO-25, which uses AMBE's sister protocol IMBE. The reason why §309 doesn't apply is that D*STAR transmissions (at least those using AMBE) are regulated as voice, not data, and §309 applies only to data transmissions. There is nothing anywhere in Part 97 that regulates what encodings we can use for voice transmissions; the only limitations presented to us by the FCC relate to bandwidth.

The FCC and Congress (and for that matter, the ITU) persist in maintaining an artificial divide between the voice and data regulatory regimes that has not been logically sustainable since digitization of voice became widespread in the late 1990s. Perhaps the best expression of this inanity is Rep. Ed Markey's proposed amendment to the Freedom and Broadband Deployment Act of 2001 (the Tauzin-Dingell Bill):

The term 'high speed data service' includes any telecommunications service delivering data, represented by a string of binary bits transmitted digitally as a series of zeroes and ones, but such data services do not include, under any circumstances, bits representing voice communications, even though such voice services are also expressed digitally as a series of zeros and ones, data services being digital bits of special importance. Someone, preferably a senior corporate employee with years of experience in analyzing zeroes and ones, shall posses authority to determine which bits are which as they zip through a network literally at light speed. All decisions of such employee may be challenged and brought to the attention of government officials, but only after a wee bit, and only bit by bit.

Rep. Markey's proposal was, sadly, ruled out of order by the committee chair. This amendment (which was clearly offered for comic value) underscores the fact that, at least in 2001, while telecommunication providers could not meaningfully distinguish between digitized voice data and other forms of data passing through their network, Congress (and therefore also the FCC) continued to operate under the assumption that they could. (For more on the Tauzin-Dingell bill, see this interesting article from llrx.com.)

Sadly, neither Congress nor the FCC appears to have learned anything in this regard since 2001; even as the FCC (and also Homeland Security) pushes commercial and public safety licensees into digital voice, the FCC continues to be burdened by an obsolete voice/data regulatory dichotomy. To be fair, much of this is forced on them by Congress, and even to some degree by the ITU (emission designators, which drive the regulatory picture at a very deep level, are based only on the superficial RF modulation technique and the ultimate payload, without regard to any intermediate encoding).

As to D*STAR itself, and its reliance on AMBE, I'll simply repeat what I said back in October: "We need to encourage the development of open digital voice standards, not make excuses for perpetuating existing closed ones just because they already exist."

Field Day 2009

2009-06-29T10:27:00.003-05:00

This weekend was my first Field Day, at least the first that I went to (I got my license in April 2008, but I didn't have any connections with any group, nor any radios of my own save a simple HT, in June of 2008 so I didn't participate in the event then). I must admit that I had a great time and look forward to doing it next year.

I had originally planned to mainly be a support person at this year's event, helping with setup, food, and so forth over the course of the event. At the last planning meeting I volunteered to co-captain the GOTA station this year (since my license is barely a year old I'm a good candidate for that) but my co-captain came down ill, leaving us with no station to operate. So I was back to helping with antenna lifts and such. No big deal.

I should mention that the club I worked Field Day with is the Du Page Amateur Radio Club, W9DUP, in northeastern Illinois. We ran 7A this year out of our usual site, the Hawthorne Hill Woods, a relatively undeveloped property owned by the Woodridge Park District. Running 7 stations means there's a lot of antennas to go up.

I reported to the site a little after 6pm Friday and helped with the first erection of the minibeam that one of the CW stations was going to use. Getting that up took most of the available daylight that evening. We took two shots at putting up the 40m/15m dipole for the other CW station but couldn't get a good position in the trees before it got too dark. That would have to wait until morning. I went home around 9pm and went to bed.

Saturday morning I headed back into the site arriving just before 9am. By this time it had been determined that we needed to take down the minibeam because there was a configuration problem with it and it wasn't tuning up. I missed the takedown, though. Most of my time that morning was spent helping get the previously mentioned 40m/15m dipole, the 80m dipole for the first CW station, and the G7 longwire that the digital station would be using up. One of our members has an air launcher that works really well and we got very good placements for all these antennas.

We got the last of these up around 12 noon, giving me just enough time to grab something to eat. After that I went over to the digital (PSK) tent because this was the mode I was most interested in anyway, and watched Bob KA9BHD try to work digital for about an hour, without a lot of luck; band conditions weren't very good, and there was just too much traffic to have much luck at working anything. I wandered around for a while, helping out with little things here and there, and ended up at at the 75m SSB table where I logged for a half hour or so for Pat K9PPP and then operated for a half hour or so before we decided that the impending storms to the west were generating too much QRN to make many more contacts and took a break. I went back after a bit and managed to work a couple more stations but the storm-related QRN was continuing to build. I wanted to go back home for a bit anyway, so I left the site again around 5:30 to go home for a few hours.

I returned to the site around 9pm just as the rain from the storm system that mercifully passed mostly south of us hit in earnest. After putting a couple of tarps over the digital tent to keep water out and deciding that the dangerous part of the storms were past, we decided to bring the PSK station back up. Marianne KC9JLK worked the station for about an hour making some contacts, then I took over around 10pm and worked it until midnight with Bryan KC9GRH logging for me until he went to bed around midnight. Activity was poor to moderate until around 11:30, then it finally started to take off.

I had not planned on working the station all night, but shortly after Bryan went to bed the bands really started to pick up. We had three antennas configured for this station, a longwire dipole that Marty got way far up in the trees for us that would tune on just about anything that I was using, which was mainly 80m, 40m, and 20m (I also tried 15m and 10m but didn't find anything to work), plus a pair of horizontal dipoles on a mast, one tuned for 40m and the other for 20m. The longwire was by far the best of the three, but it was much more suspectible to QRM from the CW operators, especially on 40m when they would turn their beam to point at my antenna and swamp me with S9+80 dB QRM.

Anyway, between midnight and about 5am I managed to work about 50 stations across all three bands, logging my own QSOs as I went and switching from band to band as the CW QRM got to be too bad or when I'd worked out the selection of who there was to work on any particular band. I took a short nap around 5am, at the operating position, then woke up in time for East Coast sunrise, which heralded a great opening on 20m and another 30 contacts over the next 90 minutes along the east coast. At 8am, when I finally broke for breakfast, we had logged 102 contacts, two over our 24-hour goal of 100. I did go back after breakfast and worked one more contact, then decided that if I didn't go home then I'd be too tired to drive safely at the end of the day, packed up and went home.

If you worked W9DUP on PSK during Field Day, the chances are good that you worked me. I had a great deal of fun, and you can bet that I'll be doing this again next year. About the only thing I think we need to do is work something out between digital and CW stations so we don't interfere with each other as much. And maybe add a second digital station.

Not dead yet!

2009-06-24T20:18:00.003-05:00

I know, I haven't posted in a while. I've been otherwise occupied, by a whole host of other things:

I've returned to working on my rewrite of MediaWiki into Java. The work is progressing much better this time. I've discovered some really glaring bugs, too, although probably most of them are uncommon code paths and so don't often affect anything. Unfortunately, the way I'm using phc as part of the translation process strips comments and destroys line number relationships, so it's difficult for me to back-relate the logic errors to the original PHP.
Sims 3 has occupied some not insignificant part of my time lately. I'm not going to comment a lot here about the Sims; suffice it to say that I think this release is an interesting addition to the franchise with enough difference from Sims 2 (which I also enjoyed) to seriously capture my interest.
It's the warm season again, and that means it's time for household projects of all stripes.

I just haven't had a lot to say here, and so I haven't said much.

See you all at Field Day.

TLS blackhole?

2009-05-28T20:23:00.003-05:00

So today I was called by one of my clients to assist with a problem they were having accessing a secured website operated by a major business data processing company (you know, those big companies that do payroll, that sort of thing). One of their accountants reported that he could access the site from home, but not from the office, and the behavior suggested to them that the issue was a firewall issue of some sort, and since I do their firewall consulting they called me.

Now, I strongly doubted that it was a firewall issue, but the facts did fit that pattern (as they had tested accessing the site from a laptop on the outside of the firewall and that worked), so I made a trip to the client site to investigate further.

Investigation determined that the laptop in question actually worked from inside the firewall as well as outside, which flatly ruled out firewall issues. I noted that the laptop was not in the domain while the computers being used to test were inside, and suggested that we remove one of the nonfunctioning computers from the domain. This did not help, and we pursued other options. I also noted that the functioning machine was running IE6, while the nonfunctioning one was running IE7. (The complaining user states that he was using the same computer at home as at work, a traveling laptop, but I believe he misrepresented that fact to us and was actually using a different home computer, which caused me to waste considerable time investigating whether there was a domain authentication issue going on). Further investigation showed that the site could be accessed with Firefox, Opera, and IE6, but not with IE7, Google's Chrome, or Apple's Safari. (No machine with IE8 was available.) After using Process Monitor (which is a most excellent tool, although it does generate great gobs of output that takes some effort to sort through) to understand what was causing the hang. This having led to the determination that the web server not responding for some reason, I decided to sniff packets using Wireshark, freshly installed on the laptop. The network traces for sessions using IE6, Firefox, and Chrome were quite illuminating.

The site in question was hanging when being presented with an https session using TLS 1.0. TLS 1.0 is enabled by default and used preferentially by IE 7, Chrome, and Safari, but is not enabled by default in IE 6. Since the remote server's response to an attempt to negotiate a TLS 1.0 session is to hang (it sends a TCP ack to the TLS "hello" packet, but no further traffic), these browsers will wait indefinitely on the stuck connection. Firefox (and apparently also Opera) apparently have programmers who have run into sites like this and have coded defensively around them: Firefox also tries to use TLS 1.0, but when the TLS session times out, it retries the session with SSL 2.0/3.0, which the web server was happy to accept. IE 6, on the other hand, works merely because TLS 1.0 isn't enabled by default in this browser.

The "solution" for my client was to disable TLS 1.0 on the affected user's computer; not ideal, but it works. It would be nice if Microsoft made IE smarter (like Firefox), or if they gave me a way to disable TLS 1.0 only for this site; or if the Large Data Processing Company would just fix their server....

Dayton approaches

2009-05-12T09:34:00.002-05:00

It's time again for the Dayton Hamvention; once again, I will not be going. I don't have the funds this year to spare for the trip and admission. And the main point of going to Hamvention (as far as I can tell) is to buy stuff, another thing I can't readily do with limited funds.

For those who will be passing through the Chicago area on the way to Hamvention, some driving advice: Do not follow I-90 all the way through Chicago. You will run into the badly congested O'Hare Toll Plaza at the end of the Jane Addams if you do this, not to mention I've heard that the west end of the Indiana Toll Road is a mess as well. You'll be better off bypassing around the city with a combination of I-290, I-294, and I-80. If you need help, there will be, no doubt, plenty of local hams monitoring on the local VHF and UHF repeaters; for example, I'm almost always monitoring the DuPage Amateur Radio Club's 2m repeater at 145.43(-) PL 107.2, and I'll be monitoring 146.52 as well starting tomorrow or so.

Oregon to ban mobile amateur radio

2009-04-24T13:31:00.002-05:00

I've discovered another state seeking to ban mobile amateur radio operation. This time, it's Oregon (link courtesy BikePortland.org). As with several other attempts by state legislatures to ban cellphone operation while driving (for example, Virginia's), this bill reaches far beyond just cell phones to ban the use of any "mobile communication device", presumably because they want to ban texting as well as talking, and using a laptop. What's especially interesting is the exemptions (quoted from the text):

(3) This section does not apply:
(a) To a person who is summoning medical or other emergency
help if no other person in the vehicle is capable of summoning
help;
(b) To a person using a mobile communication device for the
purpose of farming or agricultural operations
(c) To a person operating an ambulance or emergency vehicle; or
(d) To a person using a hands-free accessory.

So ambulance drivers, firetruck drivers, and marked (but not unmarked) police car drivers are excluded, but truckers, taxi drivers, volunteer firemen (in their personal vehicles), and amateur radio operators are not. What's interesting to me is the exemption for farmers, which makes no sense from any public safety purpose, but is clearly there merely because the farmers got to the committee before the bill got out. From various comments by legislators and others behind this bill, it's obvious they haven't thought about this much at all.

I've dropped a note to Bonnie Altus (AB7ZQ), the ARRL Oregon Section Chair, asking her what the ARRL is doing to ensure that Oregon doesn't ban mobile amateur operation.

World Amateur Radio Day

2009-04-18T14:05:00.001-05:00

Today, April 18th, is World Amateur Radio Day. Did you notice? I didn't. It's mentioned on the IARU calendar, and the ARRL ran a press release back in February, but the only press outside of the ham radio world (and even there it's getting far less attention that the fiber cut in San Jose) is a mention in the Times of India, and I can't even find that now.

It's amazing that there's no commemorative contest or something. I did find mention of one special event station (A60WARD, operated by the Emirates Amateur Radio Society, UAE), but given that people will use just about any excuse for a contest, you'd think the anniversary of the IARU would be good for one.

It seems that as a collective group, hams just aren't that good at PR.

In any case, happy World Amateur Radio Day, wherever you might be.

Always back up your data loss

2009-04-10T09:34:00.001-05:00

I bought a SATA card for an older computer I am trying to make useful here yesterday. On the front page of its manual is this choice gem:

Before installing and activating RAID function, please make sure you have a complete backup of your existing data loss due to abuse, misuse, or neglect.

Here's what I'm not clear on: if I have a complete backup of my data loss, is it really lost?

Punished for passing a code test?

2009-04-03T21:57:00.001-05:00

I was looking at the Part 97 regulations relating to transmitter power the other day, when I noticed something odd. The operative regulation here is § 97.313, which I'm going to reproduce in part below because it's hard to link to ecfr searches:

(a) An amateur station must use the minimum transmitter power necessary to carry out the desired communications.
(b) No station may transmit with a transmitter power exceeding 1.5 kW PEP.
(c) No station may transmit with a transmitter power exceeding 200 W PEP:
(1) On the 10.10–10.15 MHz segment;
(2) When the control operator is a Novice Class operator or a Technician Class operator who has received credit for proficiency in telegraphy in accordance with the international requirements; or
(3) The 7.050-7.075 MHz segment when the station is within ITU Regions 1 or 3.

(I left out the sections past (c); they relate to the various bands on which everyone has power limits.) The section of interest here is (c), and specifically (c)(2), which limits Novices and Technicians who have passed a code test to 200 W. Since the regulation doesn't specify any bands, it applies everywhere. Technicians who have not passed a code test are unaffected and therefore have the same power privileges as any other operator.

In effect, this means that Tech Plus licensees (a dwindling lot, to be sure) actually lost power privileges even as they gained emission privileges. And since there is now no other distinction in the regulations between Tech and Tech Plus, the net result of this drafting error is to limit the power privileges of Tech Plus licensees.

I am sure this is not what the FCC intended; I assume they intended to limit the power of Technicians and Novices operating in HF to 200 W. Clearly § 97.313 should be amended, to clarify that section subsection (c)(2) only applies below 30 MHz (or whatever the FCC actually intended) and to remove the reference to "proficiency in telegraphy" language that is now obsolete.

Of course, they could amend it to restrict Technicians to not exceed the powers set forth in § 97.13(c)(1). Those power limits (the limits above which the licensee must conduct an environmental evaluation) have been established as limits to ensure safety, and it would be reasonable to assume that a Technican-class licensee may not possess sufficient expertise to conduct such an evaluation properly, and on that basis restrict power levels that might endanger the public to General-class licensees or higher. But that's just an idea.

Amateur Radio Licensing Exams

2009-03-22T11:58:00.001-05:00

The ham radio sector of the blogosphere is all agog over the FCC's recent decision to deny KI4NGN's petition to expand the minimum question pool size from 10 times the number of questions on each exam, to 50 times. As best as I can figure, the argument for expanding the pool is to make it impossible for candidates to memorize the entire question pool, enabling them to pass the exam without actually learning anything. The FCC denied the petition because the petitioner did not provide evidence that the current practice was, in fact, leading to there being a large number of operators who did not possess the necessary skills to operate their stations correctly.

First, I'm one of those people who at least partially memorized the question pools, with enough success that I managed to pass all three elements at one go. I also publish study decks (derived directly from the NCVEC published pools) that, used in conjunction with readily available software, will assist others in using this technique to prepare for the exams, if they so choose. I don't have a problem with people using this approach; I want to see as many interested people in ham radio as possible. (Unlike some people. More on this later.)

Second, many of the commentators state that Mr. Mancuso's proposal would make it much harder for candidates to pass. That is something of a reach. While it would make memorizing the pools much harder (the Technician and General pools would be forced to increase to at least 1750 questions from their current 392 and 486, respectively, and the Extra pool to at least 2500 questions from its current 738), it would be entirely up to the NCVEC to decide whether the additional questions would actually cover additional material, or merely involve more permutations of the same material requiring no additional study.

Either way, however, it would have a dramatic impact on the NCVEC. The NCVEC, as the body currently charged with producing and maintaining the question pools, is, as far as I know, organized entirely on a voluntary basis. Accepting Mr. Mancuso's petition would have forced the NCVEC to come up with four to five times as many questions on each of the three pools; this would have strained the capabilities of what is presently an all-volunteer organization and would likely have required the NCVEC to hire staff, which would force them to solicit contributions from, or even charge dues to, their member organizations, which would in turn force them to increase testing fees. There are enough people complaining about the ARRL/VEC charging $15 per session; just imagine how loudly they'd screech if that went up to $30. And, of course, any increase in fees will incrementally exclude some candidates.

More importantly, however, is that Mr. Mancuso's petition underlies a misunderstanding of the purpose of the licensing examinations. The exams do not, by any reasonable standard, test candidates on whether they have the skills they need to successfully operate an amateur radio station. Some of the questions are, in fact, somewhat relevant, but a passing grade on the current exams, whether obtained "honestly" through actually learning the material, or merely by memorizing the pool, does not in any way insure that the licensee has any clue how to successfully operate their station. There is no practical test of operating procedures anywhere in the licensing process.

And that's a good thing. Why? Because such a test would invariably involve subjective judgments by the examiners. The nice thing about the examination structure we have now is that the tests are objective. The answer is right, or wrong, and there is little wiggle-room for a VE to fail a candidate for "inappropriate" reasons. There's no real way to do a practical operation test that doesn't involve subjective judgments by the VEs on whether the candidate passed or not, and as soon as you allow subjective judgments you allow for the possibility of prejudice. And that's something we just can't afford to have.

And anyway, the purpose of the tests isn't to ensure that every ham radio operator is competent at electrical engineering. The purpose of the test is to filter out people who aren't willing to take the time (in some way or another) to learn the minimum material required for the tests. The idea is that we put on the test material that we want newcomers to our hobby to be at least passingly familiar with, so that they will learn at least some of it, and by passing the test they demonstrate at least a passing commitment to learning these things as well as an understanding that our hobby has rules that everyone is expected to follow. For this purpose, the size of the pool is almost completely irrelevant; all that matters is that the questions cover the range of material that we want newcomers to be exposed to.

In short, the exams are, pretty much explicitly, a barrier to entry. Barriers to entry are always a challenge. Set them too high and you don't get enough participants; set them too low and you get people who lack sufficient attachment to the common goals and purpose of the community to feel bound to follow its rules. I think for the moment we set a pretty good balance on this issue with the current examination practices, both with the Technician (entry-level) license and with the somewhat harder General license. The more rigorous study required for General increases the likelihood that the licensee will have come to understand the importance of following the rules, which is more important for licensees with access to HF because of the worldwide propagation and much more restricted spectrum to share.

The much higher requirements for the Extra actually make sense because this is a "prestige" license; not being able to get Extra doesn't substantially exclude the licensee from much of anything (mostly, access to short callsigns, access to some of the more valuable contesting spectrum, full privileges as a volunteer examiner, and broader reciprocal privileges when traveling abroad), and so making this license substantially harder will limit it to those who show substantial commitment to the hobby, which is exactly what we want.

In my opinion, the testing system we have now is pretty close to the best one we can really hope for. We could lower standards further in the hopes of getting more hams, but I suspect we'd not get that many more active hams, just more people with licenses who don't actually use them. We could "increase standards" further by increasing the number of questions on the tests, increasing the size of the pools, or broadening the content being tested for, but that runs the risk of merely excluding people who might otherwise become licensees, without actually improving the competency of current licensees. We could institute "practical testing", but that introduces a huge opportunity for prejudicial administration of the examinations that would exclude people from the hobby for illegitimate reasons. It's certainly important that the NCVEC consistently revise the pools to ensure that the questions asked continue to expose licensees to the issues they need to be aware of, but I do not believe that any significant change to the process as it exists now would materially benefit the hobby.

Other posts on this topic that may have inspired this one:

K3NG's Just What Is the "Dumbing Down" of Amateur Radio?
KB6NU's FCC Denies Petition to Increase Size of Amateur Radio Question Pools
Various discussions on Twitter and IRC
An email from Will Sperling K9WSS that I don't think Will has posted online anywhere

Running a PC off batteries

2009-03-14T20:11:00.001-05:00

This (well, actually next) month's QST has an article on DC-to-AC inverters targeted toward the specific purpose of running a shack computer off the shack battery backup supply. While DC-to-AC inverters can be useful, there's a better solution to this problem and the QST article completely ignored it: replacing the PC's supply with a direct DC-to-DC converter.

Powerstream (a company with which I have no experience or connection) offers several DC-to-DC power supplies in the ATX form factor for very reasonable prices. Laptops and other devices with "brick" or "wall-wart" supplies typically have low-voltage DC inputs that can be accommodated either by adapting a car adapter (recall that 13.6 VDC "shack" power is essentially the same as automotive accessory power) or by homebrewing a DC-to-DC converter (buck/boost converters are one option for this). About the only devices that cannot be easily run by a DC-to-DC converter are CRT monitors and laser printers. CRT monitors should be replaced by LCDs anyway as the latter have far lower power consumption, and laser printers have such high startup currents that they probably can't be run off a DC-to-AC inverter either unless the inverter has a very high surge capacity. I've known more than one IT operation that had UPS problems caused by plugging a laser printer into the UPS.

Of course, most DC-to-DC converters use pulse-width modulation to generate the desired voltage(s), and hams will have to be careful to ensure that any RFI generated by such approaches is managed with care, and it might be difficult to do this. My main beef with the QST article is that it presented DC-to-AC inverters as the solution to the "how to power a computer off batteries" problem without even mentioning in passing that there are other solutions that at least deserve some consideration.

Battery backup for ham radio gear

2009-03-11T00:05:00.001-05:00

The second issue I heard on last Monday's TechNet (a weekly net held by the club I'm a member of) was on the topic of battery backup for repeaters and other ham radio gear. This issue was raised by Ryan (KC9OFF), and as it happens his specific situation is not going to be that interesting to hams as he is trying to provide power to an Icom FR3000 series repeater, which is not ham gear (it's business band gear) and that particular repeater already has a built-in battery controller so setting up a backup battery on it is just a matter of connecting a battery to the terminals on the repeater in the correct polarity. (I really should charge him a professional fee for researching this for him, but hey, whatever.) However, us hams tend to use gear with slightly fewer "creature comforts", which means we have to roll our own (or at least put together from components) power controllers for such thing. Not that that's a problem: rolling our own is part of what we do, right?

During the net I asserted that there was an article in November's QST on battery backup systems for ham shacks; fortunately, I was right: the article in question is on page 76 in the regular "Getting on the Air" column. That column describes two approaches to battery backup. The first approach is use an inline charger and a boost/buck regulator to provide regulated 13.8 volts to the radio no matter what voltage is provided by the charger/battery combination (which could be as high as 16 volts when the charger ramps up, or as low as 10 volts as the battery runs down). The second is to use a switching power controller that has separate inputs for charging power and the battery; the difference is that the power controller will not draw from the battery unless the main power is down, while the inline design draws from the battery and the line power (charger) to the extent that each can provide power at any time.

In the inline design, you will likely draw from the battery while transmitting, because the charger probably only provides 5 amps at most and cannot provide the full 20 amps or more that a typical rig pulls while transmitting. As long as your transmit duty cycle is low enough, the charger will have enough time to recharge the battery between transmissions. The main problem with boost/buck regulators is that the majority of regulators out there generate "noisy" DC; virtually all of them use pulse-width modulation for power control, which generates RF noise and will require significant filtration to avoid RFI issues. The switching power controller does not do this, but will present a variable voltage to the radio when switchover occurs and as the battery discharges (unless it also contains a boost regulator, in which case all the issues with those again arise).

Several people on the net noted the need to include protective hardware (mainly fuses and diodes) to prevent the battery from draining through the power supply and to protect against various sorts of possible failures that could lead to shorts. The inadvisibility of using an ordinary car batteries (which are optimized for short high drains, not for extended low drains) was also mentioned. Car batteries should never be used for backup power. There are a variety of deep-cycle options for this purpose which are designed for long-term moderate-power draws. Many are also engineered to avoid venting hydrogen gas, which would create an explosion risk when used in an enclosed space.

The solution I'm still looking for I haven't found yet in commercially available gear, and involves using solar as primary power and a battery rack as backup during the night, with line power being used to charge the batteries only if they drop below the point that they aren't expected to recharge in the sun the next day. I think I've seen a controller that supports multiple power sources, so if I put the solar panel on one input and a line supply on another, but use a switch/relay to only provide AC to the line supply when the battery voltage is below the threshold, (with some hysteresis to avoid chugging) then the system would perform in the manner I desire.

MFSK Idle Tones

2009-03-09T22:32:00.001-05:00

In tonight's TechNet (a weekly net held by the club I'm a member of) one caller (Ed, K9EW) asked about the idle tones that various MFSK implementations, given that he's noticed that different MFSK generators seem to generate different idle patterns. No clear answer was given on the net, although the discussion came to the conclusion that it was, at least to some degree, up to the programmer to decide how to do this.

The ARRL publishes formal technical specifications for some common digital modes, including MFSK. According to section 3.8 of this specification, compliant MFSK implementations must inject a non-printing character every 20 symbol periods, in order to avoid sending an extended period of a single tone. The standard does not specify which nonprinting character must be sent (although ASCII NUL, 0x00, is suggested). A programmer could elect to send any of several nonprinting characters, which would result in different bitstreams.

The reason for not allowing a extended single tone is that this would allow the symbol clock between the sender and the receiver to desynchronize. The specification requires that receivers maintain clock for at least 50 cycles, so sending a character every 20 cycles guarantees that sync is maintained as the receiver will resync its clock with each "diddle".

For more on the technical specifications of digital modes, see fldigi's excellent Digital Modes page.

The Right to Receive: Police Scanners and the Internet

2009-03-06T17:21:00.001-06:00

Last night, I ran across this entry on a blog for the communities of Clayton and Concord in California. In this entry, the publisher of the blog announced his intent to put up a live internet stream of his scanner, which is tuned to receive various police frequencies in the "ClayCord" (Clayton/Concord) area. The comments on the thread are, to be certain, very interesting, as well as rather disturbing.

The idea of streaming scanners is pretty well established. There's a whole organized system for picking up live ATC streams (LiveATC.net), which got some significant attention because the site was able to produce a recording of the communications related to the crash of Continental 3407 in Buffalo within hours of the crash. There are also quite a large number of sites offering live and recorded police radio streams for much of the United States.

And apparently the police aren't too happy about this. Several states have laws that attempt to limit people's right to receive police radio, even though the Communications Act of 1934 granted a virtually unlimited right for any person to receive any signal they can hear. Apparently the police don't want people listening to their radio signals, and rather than taking the obvious step of encrypting them to prevent people from usefully listening to them, they prefer to try to make it illegal, and when that fails, harass those who do listen to them anyway and make it easier for others to listen to them.

Some of this is evident in the linked thread: witness the several comments (probably all from the same person) declaring that the "FCC has regulations that prohibit streaming a police scanner" (they don't) and declaring other laws that make this sort of thing illegal, or which create criminal liability for the streamer should someone use their stream in the commission of a crime. Why, one wonders, are the police so insistent that the public not listen into their conversations?

Then there's the recent issue with the Indianapolis Metropolitan Police Department, which recently got itself in hot water because citizens (reportedly, amateur radio operators) recorded IMPD officers using profane language to exchange vulgar and inappropriate comments, using frequencies the police do not have permission to use. The use of unlicensed frequencies is especially concerning; the use of "unexpected" frequencies for such inappropriate commentary suggests that the officers in question knew that what they had to say was improper, but thought that, because it was being said on a "nonofficial" channel, would go unnoticed by supervisors and observers and thus not lead to repercussions. Unfortunately for them, there are people who listen to everything, and someone took enough offense to report it to the FCC.

I've heard rumors that the FCC is withholding the identities of the people reporting the unauthorized transmissions because there is a real concern that the IMPD, or members thereof, will seek retribution against the reporters. The fact that they were reported as "amateur radio operators" is especially interesting because of Indiana's mobile scanner law, which explicitly exempts amateur radio operators; by identifying the reporters as amateur radio operators that makes it impossible for IMPD to demand disclosure of identities so they can investigate whether Indiana's mobile scanning law was broken. Those of us in Chicagoland know just how bad it can be when you cross a cop: just ask Mike Geinosky, who has received 24 parking tickets in 16 months, several of them for a car he no longer owns. And that's mild for Chicago.

The clincher in that ClayCord thread was when the anonymous coward responded to my post explaining why the ECPA doesn't prohibit republishing police radio transmissions with posting somebody's address (not mine; I don't live in Concord) and encouraging people to go there and "protest" me. Fortunately, someone (probably the blog owner) quickly deleted that comment. Pretty blatant attempt at intimidation, there.

So, while there's little question in my mind that while police scanners can be used for socially unredeeming purposes, the socially positive purpose of allowing the public to better keep tabs on how well the police (who are supposedly their servants) are performing their duties overwhelms that.

Lunar repeater

2009-02-28T22:25:00.000-06:00

Image via
Wikimedia Commons

Today's outlandish ham radio idea: plop a repeater on the surface of the moon.

This came up during a discussion on Twitter, of course. The main challenge would, of course, be getting to the moon. Also, the repeater would be have to significantly larger than a satellite repeater because it would have to have a significantly higher power budget. Path loss from the earth to the moon (one way) is between 190 and 200 decibels, so a transmitter power of at least a couple hundred watts would be desired, more than can be handled in your typical cubesat.

In order to power this device, a substantial solar array will be needed, and the lander will have be developed to self-deploy the array on landing. The station's antennas will also need some way to track the earth, as we'd want to use relatively highly directional antennas for best results. Presumably all the signals will be coming from the earth, and so an antenna whose beamwidth is only slightly wider than the earth's apparent size from the moon's surface (how big is that, anyway?) would make sense. At the very least the deployment system has to find the earth initially; since the moon is tidally locked once you've found it it shouldn't move a whole lot, but I think libration movement probably exceeds one earth diameter when seen from the moon's surface and so active tracking would probably be a net gain.

This is, of course, completely impractical, but it would be fun. And probably very expensive. And the EME people would probably complain to high heaven if we ever did it.

South Carolina middle school cuts ham radio, astronomy clubs

2009-02-20T13:31:00.001-06:00

I got word today that a middle school in South Carolina has cut its ham radio and astronomy clubs, apparently in the interest of cost-cutting, even though the ham radio club operated at no expense to the school. These two clubs were the only non-sports clubs at the school.

No word on whether they cut any of the sports clubs; I'm still hoping to get more information on this.

Can someone explain to me, in the meantime, why we spend so much public money on sports for our kids, and so little on giving them opportunities to excel in science, math, and engineering?

Repeater maps!

2009-02-17T16:40:00.001-06:00

Mainly out of curiosity, I decided to map the repeaters in my repeater database coded by CTCSS. This was a bit of fun, because I had to clean the data (it's amazing how many repeaters are listed with silly CTCSS tone values like "961" or "Yes") and then figure out how to generate a map and put the data onto the map. The last bit was aided immensely by the Generic Mapping Tools, a nice little set of tools very much in the UNIX spirit. As K6HX put it to me, "it's quirky, but does a good job once you figure it out".

Click on the thumbnail to go to the full size image on my wiki.

I was kinda hoping that you could see the way some coordination councils use CTCSS tones regionally, but it's not very obvious except for a couple places, like Western Pennsyvlania, Michigan, and Wisconsin. A different color code might help here; I'll have to explore that later. I might also do another map, coloring by the majority CTCSS tone in each grid square, but first I'll have to figure out how to plot regions.

By the way, the most popular CTCSS tone is 100.0, with the next four (which trail by quite a lot) being 103.5, 123.0, 107.2, and 88.5.

I'm also really curious about the repeater out in the waters off the coast of North Carolina.

Conspiring to control space weather

2009-02-15T00:36:00.000-06:00

There's a pretty good discussion over on Watts Up With That? regarding the failure of Solar Cycle 24 to get up and go yet, something which has somewhat confounded stellar physicists so far. Given the relatively high importance of the solar cycle to amateur radio operators, or at least those who operate in HF, we tend to be aware of the solar cycle, and talk about it quite a bit.

However, what got me was the discussion about vested interests lobbying scientists to predict higher solar activity levels than the data would otherwise support; in short, the allegation that elements (at NASA or elsewhere) are being influenced to predict relatively high solar activity levels. Is there nothing that big business won't stick its big fat nose into and tamper with just to make a few extra bucks?

End of the rabbit ear era?

2009-02-13T14:19:00.001-06:00

Image by PiKimage.com via Flickr

I ran into this discussion on a blog the other day (thanks to Backtype, which I use to monitor for interesting discussions in places I might otherwise not see them). It's interesting to me how ill-informed the general population is about the analog TV sunset (which is semi-delayed now, although many places will still go dark in just a few days). The most interesting one to me is the apparently widespread belief that the converter box somehow replaces the antenna, rendering it obsolete, instead of acting in concert with the antenna.

I suspect a lot of people think that using a DTV converter box to receive TV is something akin to cable or satellite TV, probably because digital TV converter boxes resemble cable TV converter boxes in many ways. There seems to be a lack of understanding that the DTV box is receiving signals transmitted over the air in the same manner as traditional analog TV, just in a different modulation that their old TVs aren't capable of understanding. All the DTV box does is convert the signal to one that is comprehensible to an older TV that lacks the digital decoding hardware. You still need the rabbit ears or rooftop antenna; the DTV box doesn't eliminate those at all.

Another comment in that discussion I found interesting was the notion that "I don't way to pay to watch TV". Well, you presumably paid for your TV, right?

In my experience, the DTV box in conjunction with an existing antenna will actually work better than that same antenna did in analog. Of course, my experience is limited to the relatively signal-rich Chicagoland area; your mileage may vary.