Peter,
One other thing to keep in mind is that the satellite is out of eclipse during the last 2-4 minutes of each evening pass at your latitude now, so the transponder will switch off as it passes to the north. This period will grow longer and longer as we move towards the northern summer solstice.
This shows you how much transponder time you have on your evening passes tomorrow night:
14.03.2014 E 19:09:00 81.3 0.6 156.0 677 3007 39 49 1551 - 14.03.2014 E 19:10:00 73.8 2.5 158.6 676 2783 38 52 1551 - 14.03.2014 E 19:11:00 65.0 4.1 161.3 675 2608 36 56 1551 - 14.03.2014 19:12:00 55.1 5.3 163.9 673 2494 34 59 1551 - 14.03.2014 19:13:00 44.6 5.7 166.5 672 2451 32 63 1551 - 14.03.2014 19:14:00 34.0 5.3 169.1 670 2482 29 66 1551 - 14.03.2014 19:15:00 23.9 4.2 171.8 668 2585 25 70 1551 - 14.03.2014 19:16:00 15.0 2.5 174.4 666 2751 20 73 1551 - 14.03.2014 19:17:00 7.2 0.6 177.0 664 2969 12 76 1551 -
14.03.2014 E 20:42:00 134.8 1.4 144.3 680 2907 20 32 1552 - 14.03.2014 E 20:43:00 131.4 5.1 146.9 680 2522 19 36 1552 - 14.03.2014 E 20:44:00 126.7 9.5 149.6 679 2151 18 40 1552 - 14.03.2014 E 20:45:00 119.9 14.8 152.2 678 1804 17 43 1552 - 14.03.2014 E 20:46:00 109.3 21.0 154.8 677 1499 15 47 1552 - 14.03.2014 E 20:47:00 92.8 27.5 157.5 676 1270 14 50 1552 - 14.03.2014 E 20:48:00 69.1 31.4 160.1 675 1163 13 54 1552 - 14.03.2014 E 20:49:00 43.7 29.4 162.7 674 1211 11 58 1552 - 14.03.2014 20:50:00 24.4 23.4 165.3 672 1400 9 61 1552 - 14.03.2014 20:51:00 12.0 16.8 168.0 671 1681 6 65 1552 - 14.03.2014 20:52:00 4.0 11.1 170.6 669 2016 3 68 1552 - 14.03.2014 20:53:00 358.7 6.4 173.2 667 2381 358 71 1552 - 14.03.2014 20:54:00 354.9 2.4 175.8 665 2762 352 75 1552 -
14.03.2014 E 22:18:00 185.9 0.9 140.5 681 2965 357 27 1553 - 14.03.2014 E 22:19:00 188.7 4.6 143.1 680 2573 356 31 1553 - 14.03.2014 E 22:20:00 192.5 9.0 145.8 680 2190 355 34 1553 - 14.03.2014 E 22:21:00 198.0 14.5 148.4 679 1823 354 38 1553 - 14.03.2014 E 22:22:00 206.5 21.4 151.0 678 1486 353 41 1553 - 14.03.2014 E 22:23:00 220.8 29.8 153.6 678 1206 352 45 1553 - 14.03.2014 E 22:24:00 245.3 37.5 156.3 677 1034 350 49 1553 - 14.03.2014 E 22:25:00 277.8 37.9 158.9 676 1024 349 52 1553 - 14.03.2014 E 22:26:00 303.4 30.6 161.5 674 1181 347 56 1553 - 14.03.2014 22:27:00 318.6 22.0 164.2 673 1452 345 59 1553 - 14.03.2014 22:28:00 327.6 14.9 166.8 672 1784 343 63 1553 - 14.03.2014 22:29:00 333.3 9.3 169.4 670 2149 340 66 1553 - 14.03.2014 22:30:00 337.3 4.7 172.0 668 2530 336 70 1553 - 14.03.2014 22:31:00 340.3 1.0 174.7 666 2921 331 73 1553 -
14.03.2014 E 23:59:00 252.1 1.4 149.8 679 2904 329 40 1554 -
The most obvious cause of deafness is certainly alligators though. The satellite appears to be functioning fine. The FUNcube Handbook says that the AGC range of the transponder is 43 dB. Perhaps someone more knowledgeable about how transponders operate can put into perspective how that translates in real-life usage.
73,
Paul, N8HM
On Thu, Mar 13, 2014 at 7:02 PM, Patrick STODDARD (WD9EWK/VA7EWK) amsat-bb@wd9ewk.net wrote:
Paul,
I had replied directly to Peter earlier today, and we have had a nice exchange discussing what he reported and what I saw on passes last night. I can expand on what I saw last night on two AO-73 passes...
The pass you referenced was a 58-degree western pass around 0535 UTC. Unfortunately, I was the only one on the transponder (as W1AW/7), so I did more tests with my transmitter power. I was able to cut my power down from 5W to 500mW and still hear myself loudly and clearly through the transponder. And it was nice outside (around 68F/20C at 10.35pm local time). The 145.935 MHz telemetry downlink sounded loud, but I did not copy it with the software (my laptop was not out with me).
At 0401 UTC, an eastern pass with maximum elevation of 11 degrees where I lose the first 3 or 4 degrees in that direction due to mountains, I had a hard time getting through in the first couple of minutes. I heard a QSO on the transponder, and one station was very loud. I was able to finally hear myself at the center of the transponder, and make one QSO (as W1AW/7) with CO6CBF. I didn't move around to find the other station, so my only QSO on that pass was with Hector.
For both passes, I used a pair of FT-817NDs, transmitting at 5W to my Elk handheld 2m/70cm log periodic (except for part of the western pass where I cut my power to 500mW).
The suggestion of trying VO-52 in particular is a good one. If the setup works for VO-52, it should do fine with AO-73. I'll be on at least one AO-73 pass this evening as W1AW/7 (0423 UTC, maximum elevation 19 degrees), and - if anyone will be up for the later pass - I will stick around for the 0559 UTC pass (maximum elevation 33 degrees). Or maybe I will swap antennas on the later pass, going with something other than the log periodic...
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/
On Thu, Mar 13, 2014 at 3:20 PM, Paul Stoetzer n8hm@arrl.net wrote:
Peter,
Not any evidence from Europe, but WD9EWK reported good downlink signals from AO-73 on a westerly pass from his QTH in Arizona while running just 500 mW to an Elk antenna last night.
The AAR29 AO-73 log page also reports several QSOs from Europe today: http://aar29.free.fr/sat/ao73/ao73log.php
Have you checked VO-52 and AO-7 Mode B passes to rule out a problem on your end?
73,
Paul Stoetzer, N8HM Washington, DC
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