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Tuesday, June 27, 2006
Out to launch 
| | The mission is NROL-22, out of the National Reconaissance Office. It should be visible from much of the Southwest as it lauches over the Pacific to the South and into a polar orbit. After a day of oddly rain-threatening overcast sky, the heavens have cleared. Visibility is, as the pilots put it, severe clear. |
| | 0326 GMT (11:26 p.m. EDT Tues.) |
| | Approval has been given to proceed with the countdown for liftoff at 0333 GMT. |
| | Okay, it went off on time. We shot lots of stills and a videotape that I'll have up on YouTube pretty soon. |
| | At 8:52pm an odd blue-ish cloud hovers in space. Nice. Right next to Jupiter, too. |
Adventures in DIY radio
| | Mary Lu points to a report to the FCC that confirms what she and others have long suspected: that most of the FM transmitters sold to play iPods and the like over FM radios are out of compliance with the FCC's Part 15 rules. |
| | Those rules provide for a limit of .25mv/m (or 48db/u) of field strength at a distance of 3 meters from the transmitting antenna. |
| | Of the sixteen wireless devices tested, only four passed. The rest put out too much signal and/or a signal that committed other violations, such as spilling over into adjacent channels. |
| | Mary Lu is pleased with the findings: |
| | Why is this important? The FCC (known as the Federal Communications Commission) is entrusted by Law to protect the public from improperly manufactured devices, and to protect the broadcast frequencies, known as the spectrum for proper use by their proper trustees, like broadcasters, cell phone companies and Amateur Radio. When devices like the transmitter are not tested, it is normally because of sloppy manufacturing, or because some manufacturers either do not know the law or refuse to abide by the law until caught. |
| | From my perspective this situation has been going on far too long. I have personally spoken to the FCC numerous times about enforcing the testing and compliance regulations for years. I urges the FCC to enforce its Part 15 rules to these transmitters and protect the public¹s right to use and enjoy the free over-the-air radio broadcast services. |
| | I understand and respect Mary Lu's concerns. But I don't know of a single instance where reception of licensed stations has been harmed by one of these little transmitters. Moreover, I own two of the tested devices — the Belkin TuneCast II and the Sirius Sportster SPTK2 — and the original iRock, which is an ancestor of the tested iRock 450FM. All three of those devices failed the test (by being too strong). In practice, however, the iRock and the Belkin are so weak they verge on useless. The Sirius is, I'll agree, pretty strong. For those reasons, I add missing antenna lengths to the iRock and the Belkin (here's that hack, with much more background on the matter) and subtract it from the Sirius, which is also capable of transmitting on 87.7 and 87.9, which are below the used parts of the FM band which most digital and analog receivers are capable of getting. The only station in the country, in fact, licensed to 87.9 is a little (10-watt) station at St. Francis High in Mountain View, CA. Channel 6 audio is on 87.75, and can either interfere with one of these transmitters, or receive interference from them. |
| | But I suspect there are approximately zero problems in this exceptional condition, since even the relatively powerful Sirius radio is blown away at 87.9 by either Channel 6 audio (which I pick up from the station in San Luis Obispo when I drive through that area between here and San Francisco) or by legitimate FM stations on 88.1. In urban regions such as Los Angeles, which are packed wall-to-wall with strong signals (starting with KKJZ on 88.1), most of these little transmitters are at a huge disadvantage. |
| | And let's not even visit the fact that computer systems all over the place produce signals that splatter all over the FM and AM bands. Ever try to listen to a radio in a hotel room or an office building? Hit SCAN and see where it stops. You'll be lucky if you can get AM radio at all. |
| | Also, many (perhaps most) FM radio also transmit a blank signal 10.6 or 10.8 MHz above and below the received signal. Tune a radio to 88.1 and you'll hear a signal with dead air on 98.9. If there's a real station on that channel, and you want to hear it on another radio nearby, there's a good chance it's getting interference. This, by the way, is why FM radio listening is forbidden on airplanes. Aviation bands start right above the top of the FM band, and can get interference from FM radio listening. |
| | Two more issues worth talking about. |
| | One is the fact that Congress and the FCC have done more to make "free over-the-air radio broadcast services" unattractive than a million little FM transmitters ever could. Between relaxed ownership rules and increased "indecency" fines by the FCC, the AM and FM bands have become boring beyond endurance. I have my problems with satellite radio too (for all their diversity, all the channels on both services are owned by one company apiece, and the two silo'd systems are entirely incompatible); but my Sirius radio provides infinitely more usefulness than I can even imagine getting from "free" radio today. All that's left for me on "free" radio are our local AM news station and NPR/PRI programs, most of which I get now via Sirius or podcasting. |
| | The other is listener independence. The great Scoop Nisker said "If you don't like the news, go out and make some of your own". That's what's happening in media today, and it's going far beyond news, and even music. These little transmitters play a small part in that revolution, and I applaud their manufacturers just for trying. |
| | Also, we're gradually escaping from the confines of artificial scarcity based on the notion, developed during the 1920s and leveraged ever since, that bandwidth — both wired and wireless — is naturally scarce. It isn't. |
| | Yes, we do need responsible approaches to service and interference. But I think we would hae yet another reversal of sensible priorities if the FCC clamped down on tiny FM transmitters. |
| | Here's a thought: get the FCC to require good radios. The receivers in most cars are okay, but the ones in portables and home audio systems are worse than terrible. |
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Troublecursing
| | So we're living out of suitcases in a house up the hill from the house we're not done building. The only electrical service working so far in the new house goes to a wall outlet used by the the cable modem, which provides Internet service to our temporary home by way of 250 feet of ethernet that runs through woods, weeds and landscaping. |
| | Getting the workers to respect the ethernet cable is an effort as wasted as trying to get them to notice the difference between the garbage and recycling cans. A few days ago, the pavers working on the driveway got the ethernet out of the way by kinking a section of it into a little ball and shoving it under the loose edge of an outdoor lighting fixture. About a foot of the cable was crimped, folded, flattened and wedged into the kind of space you'd find behind a shingle. The connection still worked when I straightened it out; but download speed had dropped from 5Mb to 1Mb. This morning it's either gone or barely there. I'll need to get a new one. |
| | Did I mention that our temporary home is also being renovated by the landlord, and workers come and go from this place too? O ya. |
| | Right now I'm borrowing packets from a source named "linksys" provided by a generous neighbor who I'm sure has no idea they're helping us out. It's a faint signal, but it gets the job done, if I don't mind sitting in the one corner of the one room where the signal gets in. |
| | Later today I'll buy another 200 feet of Ethernet (the last 50 is a separate section which I'm sure is fine). MarVac only charges $23.95 for 200 feet of Cat5, which is a helluva deal. |
| | At least we can see the beginning of the end of the waiting, though. Originally we'd hoped to be in by last Christmas. Now we're looking at August 1. |
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