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Cosmos-1 false reading



Hi gang,

Just to record an experience in monitoring for the Cosmos-1 tx on 401.5275.

I set up with my AR8000 set to CW to detect a carrier on this freq. and
took the audio out, to measure the beat frequency with SPECTRAN. Looking at
the geography of the monitoring sites, the 80 degree inclination for the
orbit and the Earth's rotation at around 22 degrees per orbit I assumed
that the satellite would be at high elevation to the SW at 21:21 UTC when
they were expecting to detect the carrier in Prague, so I pointed my fixed
3 element linear  yagi vaguely over  here (this is how I get the 9k6 data
dumps on 70 cms)

Sure enough, at 21:15:59 I detected an audio beat frequency descending very
rapidly (900 Hz in 30 seconds) and screen dumped it. I noticed it had two
sidetones 50 Hz  above and below. This rate of change I thought at first
was doppler so I was very pleased (It worked on HAMSAT). At 21:16:45 the
tone was 500Hz and at 21:16:56 about 190 Hz. Great! I thought. A little
early, but maybe a little lower in orbit than predicted.

Unfortunately the tone then went UP at the same rate, reaching 600Hz at
21:17:24, 1kHz at 21:17:39, and 2.5 kHz at 21:18:37, 2.7 kHz at 21:18:45
and 3.5 kHz at 21:19:18, where it crossed a steady-ish set of two tones 20
Hz apart on 3.3 kHz. .At 21:19:40 the rising signal had reached 3.996 kHz
and the other pair at 3.25 and 3.27  kHz. They continued  around there and
I stopped monitoring.

I'm just putting this on the record beacuse I read that the team in Prague
had detected some anomolous signals around about the time in question, and
maybe I heard them too, or that in fact (more likely) I was recording
birdies from somewhere, although I couldn' t reproduce it when I tried.

If anyone would like the scren dumps then please email me at 

g0sfj  AT  amsat DOT org 
(using the correct format for AT and DOT)

QTH is Central England, IO92NL.

73 de andy G0SFJ
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