Unlike a cosy shack, the temperature of a satellite can change dramatically during the orbit.
+30 degrees down to -20 degrees C is not unusual for a 1U cubesat and you will get drift as a result.
As the satellite size increases and you have more solar cells, (and thermal mass) you may be able to devote more power to keeping the frequencies stable....It's all a trade off which sometimes works but sometimes does not.
73
David G0MRF
To: amsat-bb@amsat.org
Sent: Mon, 29 Aug 2022 19:39
Subject: [AMSAT-BB] Re: Linear Tuning and Doppler
On 8/29/22 12:53, Calvin McDonald wrote:
> Why are the transponders not designed to hold the frequencies more exact??
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