[amsat-bb] Re: AO-73 Doppler

[Chris Thompson]

thanks Joe,

Someone else sent me a note off list to the same effect.  It makes it hard
to track when using a narrow band receiver, such as a normal radio.  I've
got the hang of it now, once I realized that the frequency would vary
depending on the temperature.

thanks

Chris


On Wed, Apr 2, 2014 at 5:12 PM, Joe Fitzgerald <jfitzgerald at alum.wpi.edu>wrote:

>
>
> > 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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-- 
Chris E. Thompson
chrisethompson at gmail.com
g0kla at arrl.net