Clayton,
I have been watching it shift 5-10 KHz or so on some passes, though 3-5 KHz is more common. Watching it with a DSP rig allows you to compensate.
The more interesting question is what, if anything, the uplink is doing? I got up for a 0200 L pass to experiment, and there was nobody else on. I thought I had it figured out, and suddenly the downlink shifted. Then, my uplink data seemed wrong, as if it also shifted. ;( Will try again the next time I have some insomnia.
73s,
Alan
WA4SCA
<-----Original Message----- <From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Clayton Coleman <Sent: Monday, September 08, 2014 10:54 AM <To: AMSAT-BB <Subject: [amsat-bb] SO-50 & frequency stability as of late < <I have been noticing some irregular shifts in SO-50's downlink <frequency the past several days. I noticed it in the past but it's <been a while since this occurred. Several others are reporting it as <well. < <At my AOS today (15:12 UTC, orbit # 62976), SatPC32 had predicted the <downlink to be near 436.801 MHz, when in fact I was receiving the bird <at 436.793. It proceeded to jump up to 436.795 at my TCA before <making it's way down to 436.780 near my LOS. < <This seems to be posing some issues for people using full computer <control and also those who stick to pre-programmed memory channels to <make frequency adjustments during a pass. < <Considering this recent frequency instability, I would recommend you <manually tune for the strongest downlink frequency. This would help <eliminate some issues with stepping on stations engaged in existing <QSO's. An alternative would be to try using RIT if you insist on <computer control. < <The old rule applies -- if you can't hear, don't transmit. < <73 <Clayton <W5PFG <_______________________________________________ <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: http://amsat.org/mailman/listinfo/amsat-bb