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Re: YABSQ (Yet Another Beginner's Stupid Question)


Even correcting for Doppler and looking at the frequency of the beacon as 
referenced to the satellite (not the ground) the beacon seems to be off 
nominal by several Khz. For example, last night I tracked the beacon for 
over three hours - at AOS I had the Satellite Frequency for the Beacon as 
2401.325900, by the end of 3 hours the frequency was 2401.325000.

So there is some drift over time

With my radio tuner I calculate the frequencies at the Satellite as well as 
the Ground. From what I have gathered the concensus seems to be that the 
beacon is at 2401.323. But I have been finding it slighly higher for the 
last several weeks. My reference point (for others interested) is putting 
the telemetry tracking point at about 1600 hz using AO40rcv (so there is a 
bias here) I don't know where the carrier is with this telelmetry 
modulation scheme? Is it really in the middle and the tones we see with no 
modulation are plus and minus 400hz?

Jerry, W6IHG

At 08:55 AM 8/17/01 -0500, Gerald Payton wrote:
>I was NOT clear on the second question.  The "drift" was not a good word.
>What I am describing is: each time (day) that I attempt to listen to AO40. I
>find the telemetery at a different freq.
>I assume that the day's heat (It's HOT in Texas) causes the d/c to change.
>Once accuired, it stays as it should normally (dot doppler.)
>If the MB is at a different frequency each time that I fire up the radio,
>the rest of my displayed frequencies will also be off from the actual
>frequency.  In short, I don't have a clue to what frequency I actually am
>on.  How could I accruately record and/or report what frequency of a QSO.
>I know some commercial antennas, radio and astronomy, cool their equipment
>for frequency stability and accuracy.  I can't afford something like that
>and also know that you experts out there don't have the same problem.  I
>asking for a solution.
>Thanks for all the replies .... I've got to go through all them now and
>figure out what's next.
>Jerry  N5GPC
>Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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Dr. Jerry R. Pixton, PIXOS Designs LLC

Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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