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Wednesday, June 29, 2005
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 Wednesday, June 29, 2005
started 6/29/2005; 1:26:22 PM - last post 7/4/2005; 11:46:18 PM
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Doc Searls - Wednesday, June 29, 2005 
6/29/2005; 5:26:22 PM (reads: 37902, responses: 6)
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WiFi4NY 
Following the money
Cluestick fungo
Loose links
| | Found here that a podcast of my Syndicate closing keynote is up. I'll have the accompanying slides up today. |
Google is a Windows company
| | Yes, Google has what is probably the world's largest Linux back end. But when it makes client applications, it makes them for Windows. Desktop search, the Toolbar, Picasa and now Google Earth are all Windows-only. At least a Mac version of Google Earth is promised. But given the predilictions behind these other tools, I'm not holding my breath. As for Linux or cross-platform versions for any apps or tools (other than ones that work in any browser), there's little evidence of interest. |
| | Yes, I know that it only makes sense to make client software first for the platform with nine out of the ten slices in the market's pie. But it's that tenth slice that keeps the company making the other nine from enjoying a monopoly. At fighting Microsoft's client monopoly, Google isn't helping much. Quite the contrary, in fact. |
| | I hate that Google doesn¹t wait to release software on all platforms simultaneously, as they are an Internet company, and I think being an Internet company means keeping the Internet free, not locking it down to one Operating System. |
Flat armadillo leverage
| | Follow-up from Dave: Didn't have to go to Radio Shack, I had such a cable, and Doc is right, it works. Glad to help. :-) |
Life in credit card silos, cont'd
| | The class action suit claims that ALL account holders that may have been exposed to a breach should be notified - whether fraud has occurred or not. |
| | The distinction here is important: Until this point, US law has defaulted to the idea that the individual does NOT own the information a company possesses about them (via interaction), but they do have rights of control over that information. UK laws are quite the opposite (they emphasize ownership). |
| | This argument is actually an argument around the *control* aspect: do I, as an individual, control my account to the extent that I can demand to know whether or not a potential breach has occurred? Or do I not control it that much? |
| | If ownership is not the issue (as it is *not* under current laws), then *where* are the lines of control drawn? This is one to watch. |
Little FM transmitters
| | And btw, to Archos, you should really have a mini FM transmitter. Every high-end MP3 device should have a good one built in. Do the Belkin ones work worth a damn? I bought an El Cheapo brand transmitter at Target (it was all they had) and it didn't work. The signal was too weak. |
| | Okay, here's the story on little portable FM transmitters. You can read the details or go straight to my simple fix for the weakness problem, after the indented section below. |
| | First, they have to be weak. That's to comply with Part 15 of the FCC rules and regulations, which restricts the ability of devices to cause interference with legal signals, especially those of licensed radio stations. The limit is .25mv /m (millivolts/meter) of signal strength into a quarter wave antenna (roughly what you've got with a typical whip antenna on your car) at 3 meters from the transmitting antenna. That's a near-fringe signal. For an example, here's the predicted coverage for Boston's WBUR/90.9fm. The red line is 2.5mv, or "local" coverage. The purple line .5mv for "distant" and the blue line is .15mv for "fringe." So, .25 falls between "distant" and "fringe" at three meters from the transmitting antenna. |
| | Now, the inverse square law does apply. That means the signal strength can be half the value at twice the distance: .125mv at 6 meters, .0625mv at 12 meters and so on. A good FM radio will get a listenable signals in mono down to .003mv (3 microvolts) and even less. That's what you'd get, under ideal conditions, at about 200 feet from the transmitting antenna of a signal that's legal under Part 15. |
| | Now, in nearly all of the urban and suburban U.S., you will find a signal of .003mv or better on every channel from 88.1 to 107.9. In most of those areas, the dial is packed with strong signals that that obliterate weaker signals on nearby frequencies. Which means that you'll need a strong signal from your little transmitter to compete, even if your transmitter is in the car and the interfering signal is coming from 30 miles away. And, if you're travelling, you'll need to keep switching to relatively open frequencies. |
| | Credit where due: car radios are made to work under less-than-ideal conditions, and are, as a rule, much better than the FM receivers in most home audio systems. (Years ago, manufacturers of home audio systems cared about FM. Now they don't. They think you only listen to CDs and surround-sound Video. To them, FM is old hat. It has tail fins.) I rent a lot of different cars, and I haven't found one yet with a bad FM receiver. (Lots that are hard to use, but none that are bad.) |
| | I don't know the transmitter power of a typical portable FM transmitter, such as the Belkin Tunecast II, which I've been using for the last year, but it's very low. In my house I also have a Ramsey FM-100, which puts out .25 watts; and I'd say the Belkin puts out a fraction of the Ramsey's signal. But that's at least partly because it lacks a good antenna. Rather than an external antenna, it uses the audio input cord, which is only a few inches long. More about this below. |
| | Licensed radio stations come in a variety of classes, but run up to 100,000 watts and more, radiating from the tops of mountains, skyscrapers and towers up to 2000 feet high (which are quite common on the South and Midwest). The weakest "local" stations have a maximum power of 3,000 watts at 300 feet above average terrain (though they drop the power on a sliding scale when the antenna height rises above 300 feet). Noncommercial stations (those below 92MHz on the dial, with a few exceptions grandfathered in the commercial band) operate with powers as low as 10 watts, though many are quite huge. KQED/88.5 in San Francisco is 110,000 watts, and radiates from a mountaintop, making it by far the biggest station in the Bay Area. Yet here in Santa Barbara, the top public station is a 4-watt "translator" on 102.3 of KCLU/88.3 from Thousand Oaks. Translators operate between one and hundreds of watts. |
| | In any case, a little FM transmitter has a lot to compete with. |
| | Make the antenna longer by adding a headphone extention cord: female at one end and male at the other. Put it between your audio player (iPod, Archos or whatever) and your transmitter. Stretch it out. The signal increase is remarkable. My Belkin TuneCast II is useless without it, and a workhorse with it. Here's one that Radio Shack sells. |
| | One more thing. These little transmitters blow through their AAA batteries. When traveling, be sure to use the car power adapter (the Belkin comes with one). |
discuss
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Rod K - Re: Wednesday, June 29, 2005
6/29/2005; 7:37:15 PM (reads: 1268, responses: 1)
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Hi Doc,
Great explanation on the FM transmitter thing.
One question about improving the performance via extending the input line cable, what do we non-Windows folks with iPods and iTrips do? We can't extend our little transmitters because they have that weird iPod connector that also provides the power for the transmitter.
Damn I hate being in that 10th slice of pie sometimes :)
I'd hate to have to switch from my Griffin iTrip back to my Canakit.
http://canakit.com/Contents/Items/CK222.asp
Rod
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Doc Searls - Re: Wednesday, June 29, 2005
6/30/2005; 1:50:26 AM (reads: 1290, responses: 0)
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Windows isn't the issue at all. We're dealing with the physical layer here — of the portable device.
I haven't played with the iTrip. The first generations of mobile FM transmitters (like the iRock, which I have) only gave you a choice of a few FM channels. Not good enough. I see the iTrip lets you select any channel. That's good. What isn't good is the lack of any way (that you or I can see) to hack the antenna.
Maybe the iTrip overcomes its lack of antenna with a stronger transmitter. But ... I don't know. I'm guessing the range won't be very good.
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Eric Eggertson - Re: Wednesday, June 29, 2005
7/1/2005; 9:14:37 AM (reads: 1104, responses: 0)
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Thanks for the link to my Modest Proposal, and for the explanation about the FM transmitters. Made my day, and taught me something I knew absolutely nothing about!
Eric
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Ian Eiloart - Re: Wednesday, June 29, 2005
7/4/2005; 2:31:35 PM (reads: 1092, responses: 0)
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No! You've got the inverse square law all wrong. That sentence should read "That means the signal strength can be one quarter (one fourth) the value at twice the distance: .125mv at 6 meters, 0.03125mv at 12 meters and so on. "
What you're describing would be an inverse law, not an inverse square law. Fortunately, the link you've provided does describe it correctly.
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Paul Mison - Re: Wednesday, June 29, 2005
7/5/2005; 2:00:04 AM (reads: 1067, responses: 0)
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Although not directly related, it's perhaps worth noting that *any* FM transmitter is illegal to use in the UK without a full-blown broadcasting licence from Ofcom, so any manufacturer of digital audio players would have to eigther forgo EU sales, or build two versions (one for the EU and one not).
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George Lowry - Re: Wednesday, June 29, 2005
7/5/2005; 3:46:18 AM (reads: 1401, responses: 0)
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I'm late to the party but wanted to share my experiences with _three_ of these devices.
I had an adapter that looked like a cassette tape with a cable tail. The adapter had a playback head inside that coupled with the playback head in the in-dash unit. Great fidelity, better than any of the over-the-air units so far. Unfortunately, the mechanicals inside the pseudocassette would jam, causing the tape player to spit it out. An uneeded distraction on Westbound I80 in the morning.
First a reference to Doc's mention of inverse square. I'm driving a Ford Expedition (I need the room for work gear; radios, hand tools and the like.) The broadcast radio antenna is silk-screened on the passenger side rear window. About as far away from the signal source as possible.
My work takes me from the Sierra foothills to the bay area a couple of times a week. I traverse probably three radio markets, with several instances of channel reuse between points A & Z.
My first try was a Sakar I-Concepts EWT-950 from the bargain bin at OfficeMax. It was cheap and covered the whole FM Broadcast band in three steps of a slide switch. Within the range of each switch stop there was an analog control to dial in the frequency desired. The audio cable was barely a foot long. I'm guessing the cable length is chosen to keep the transmitter within Part 15 limits. Based on the miserable signal strength, it had to be abundantly legal. Impressive battery life on two AAA cells seems to support that. The other wrinkle was that since the car radio is synthesized, landing only on the channels spaced each 200 kilohertz, you needed a safecraker's touch on the tiny analog (varactor?) control. The weak output and changing signal environment had me twiddling about every other county line. Again, divided attention on I80 = not good.
Second time around was the Belkin TuneCast with the LCD display. I was still operating on the assumption that full FM band coverage was an absolute requirement. Nice design, digital frequency selection, shorty cord and a battery hog. The tipoff to the power consumption should have been the fact that a cigarette plug power adapter is included in the blister pack. Even with the ability to suck dry a set of batteries in one trip to SF and back, the Belkin managed to be a "peanut whistle".
Kevin Kelly on his "Cool Tools" site turned me on to this little guy.
http://www.kk.org/cooltools/archives/000855.php
The whole thing plugs right into the cigarette lighter plug, eliminating batteries altogether. The claimed ability to play MP3's right out of a UB flash drive seemed cool. There is also a connector on side to allow connecting iPod's, CD/MP3 disc players, whatever.
I was at first concerned about the limited number (7) of transmit channels, all down at the "public broadcasting" end. Once upon a time this area had lots of open channels even in most metro areas. The combination of traditional public stations and religious stations licensing translators and even whole new licenses (witness KQED/KQEI) have pretty much chewed up those vacancies. I needn't have worried. It turns out the the limited number of channels is plenty and simplfies use to boot. This unit captures (covers up) all but the strongest local stations in my experience. Since the adapter cable is not even attached when you (try to) play from the USB port, you have to wonder how the RF escapes. It finally dawned on me that the signal is getting pumped into the plus 12 volts of the car, probably illuminating the whole vehicle. The MP3 player has some problems, it quits randomly, requiring a power down reboot (pull it out, push it in). If you don't plan on using that feature, the VR3 is a hot setup. I found mine in the automotive department at Wal-Mart.
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