[amsat-bb] Re: AO40 12m WAV files

[Bob Bruninga <bruninga@xxxxxxxx>]

Here are 3 new 5 minute WAV files.  Keep this discription:

Remember, Receiver is 1km away, so recevier controls are all by RS-232.
I tested my AGC and here are the results.  I can only sample AGC via
command so nothing fastter than a few second rate..

1) With AGC set to FAST, the AGC samples between 1F to 8C
2) With AGC set to Medium the AGC "level" samples between 46 to 6A
3) With AGC set to SLOW, the AGC "level" samples between 56 to 5F
4) With AGC set to OFF , the AGC "level" samples at 01 always and the
audio is at least 6 to 8 dB stronger.  

THus I conclude that I do have AGC OFF.  But I did record one at SLOW to
see if this will prevent any amplitude limiting that may have been going
on.  I have NO remote control over RF gain.

The amplitude fluctuations (spin AM modulation) I see on my oscope are
consistent at all settings above at least to the eye, but the AGC OFF case
is clearly at least 6 dB stronger.

Recording A at 20:10:30 AGC OFF and had high UP doppler
Recording B at 20:15:30 AGC OFF and had high UP doppler
Recording C at 20:25:17 AGC SLOW had 0 doppler for 1st 3 minutes!
Unfortunately I did not anticipate this and so I started it LOW
like the other passes and then after 3 minutes, the geometry was such that
it began going even lower.  SO I did BUMP up the doppler tunning by about
400 Hz at the 3 minute point and then again another 400 Hz at about the 4
minuute and 10 second point...

Download from:   http://web.usna.navy.mil/~bruninga/ao40TlmAudio/
  
DATE   TIME     MA   RANGE Doppler  FILE
15 Feb 20:10:30 246  14100 37020    AO40-2001-02-15-A.wav
15 Feb 20:16:30 247  12677 38380    AO40-2001-02-15-B.wav
15 Feb 20:25:17 249   9710 40030    AO40-2001-02-15-C.wav

de WB4APR@amsat.org, Bob

APRS LIVE pages     http://web.usna.navy.mil/~bruninga/aprs.html
APRS SATELLITES     http://web.usna.navy.mil/~bruninga/astars.html
MIM/Mic-E/Mic-Lite  http://www.toad.net/~wclement/bruninga/mic-lite.html



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