Yes it is off freq (often) and by the amount you mentioned. I'm guessing it is thermal. 73, N0AN
Hasan
On Sun, Nov 3, 2019, 1:43 AM James Pierce via AMSAT-BB amsat-bb@amsat.org wrote:
The last couple of passes I’ve chased AO-85 over Australia the downlink is appearing about 2.5Khz lower than expected.
I am uplinking at 435.170 and was expecting the downlink at 145.978.6 … however it seems the return is arriving at more like 145.976.1- The signal coming back is excellent once tuned, especially while the bird is higher in the pass. And yes, for anyone wondering, I use macdoppler for full doppler tuning through the whole pass.
Can anyone shed any light as to what may be happening? I’ve always found AO-85 to be a very quiet bird over Australia, and I wonder if this may be part of the reason.
James - VK3VJP _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb