http://www.amsat.org/amsat/sats/n7hpr/lo19.html
This looks pretty easy and fun.
AE5FT / Gene tried step one this afternoon.
1) Tune an HT or another 440 MHz rig (preferably with an outside) to 437.127 MHz. (or 437.125 if that is as close as you can get.) FM simplex. Turn your squelch OFF. You're going for a signal that sounds like the mp3 file at the Brainwagon blog: http://brainwagon.org/2008/01/20/decoding-lo-19-telemetry/
(I've been able to copy this signal from the easy chair before. But I get hung up here 'cause of the code.)
So you don't leave the radio on all day, here's some flyby times for Tulsa.
ate (UTC) | AOS (UTC) | Duration | AOS Azimuth | Maximum Elevation | Max El Azimuth | LOS Azimuth | LOS (UTC) |
---|---|---|---|---|---|---|---|
21 Jan 09 | 10:01:07 | 00:13:58 | 25 | 27 | 81 | 166 | 10:15:05 |
21 Jan 09 | 11:40:30 | 00:13:54 | 0 | 29 | 305 | 221 | 11:54:24 |
21 Jan 09 | 19:43:42 | 00:03:16 | 64 | 1 | 51 | 38 | 19:46:58 |
21 Jan 09 | 21:15:59 | 00:14:11 | 140 | 31 | 86 | 359 | 21:30:10 |
21 Jan 09 | 22:55:24 | 00:14:04 | 195 | 27 | 252 | 334 | 23:09:28 |
22 Jan 09 | 09:30:44 | 00:12:16 | 35 | 14 | 95 | 147 | 09:43:00 |
22 Jan 09 | 11:09:13 | 00:14:51 | 8 | 60 | 290 | 204 | 11:24:04 |
22 Jan 09 | 12:50:32 | 00:08:54 | 340 | 6 | 298 | 265 | 12:59:26 |
22 Jan 09 | 20:46:01 | 00:12:38 | 122 | 17 | 63 | 7 | 20:58:39 |
22 Jan 09 | 22:23:48 | 00:14:57 | 177 | 55 | 260 | 343 | 22:38:45 |
2) Take some really good notes of the three-character groups that come after the E LUSAT HI HI intro. (Or, try some screen shots of a waterfall or oscillograph display from your sound card ham software or Audacity podcast software.)
3) There is a lookup table to go from the letters to telemetry values (numbers).
4) Then, you put the numbers into some formulas to scale them into voltages and temperatures in the satellite.
Which sounds pretty cool. You can see what's going on in the belly of the beast. I'm going to get set up to repeat this process. If you beat me to it, send me your screen shots and I'll give you hand with the rest.
I wonder how difficult it would be to homebrew something like this bird ?
73
Scott
KD5NJR
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