I used an Alinco DJ-X11T receiver in SDR mode to record an 80 degree ISS pass at 13:33:53 UTC this morning. The packet signals did appear on the expected frequency given Doppler shift (centered on 145.825 MHz).

However, there does appear to be an issue with the packet transmissions. Scott's Dropbox image of the pass over several minutes compressed the packet transmissions to the point that the issue is not visible in his image, but it is quite apparent in my waterfall which only shows about 20 seconds at a time in KGSDR. Namely, the centerlines of all packet transmissions describe a "J" shape, even at AOS and LOS when Doppler should not be noticeable at all. In other words, there is a rapid increase in transmitted frequency at the start of a packet transmission, and this frequency change rate diminishes toward the end of the transmission. This phenomenon could very well cause some receiving systems to fail to decode packets.

I tested my system against local terrestrial packet stations just prior to the pass, and the packets show vertical lines in the waterfall, so this is not some systemic issue in my receiving system.

Todd AL0I