[amsat-bb] Re: AO-73 Doppler

Joe Fitzgerald jfitzgerald at alum.wpi.edu
Wed Apr 2 14:12:51 PDT 2014

> I notice that the frequency calculated by MacDoppler is slightly off from
> the frequency that I hear the telemetry at.

AO-73's transmit frequency drifts around as the spacecraft warms and
cools.  I remember being surprised to see the telemetry trace increase in
frequency on my waterfall display when my receiver was at a fixed
frequency.  I initially  thought something was wrong with the local
oscillator in the radio, but my signal generator showed a nice straight
vertical line.

There is likely nothing wrong with your setup.

-Joe KM1P

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