For what it's worth, since the Russian space littering event, I am getting almost daily Close approach alerts on PCSAT (is a high orbit, originally 800 km high). Alert miss-distances seem to be on the order of 200 to 500 meters Example Alert below at end..
Another day in space (after 20 years for PCSAT Semi-operational: http://aprs.org/pcsat.html Live downlink (W3ADO-1): http://www1.findu.com/cgi-bin/pcsat.cgi One minute serial nos (T#xxx), suggest a wake from1 to 8 minutes per orbit. PCSAT is unique in that is has no CPU or Operating system. It is just two off- the-shelf KPC9612 TNC's (chips in sockets, etc) and uses their built-in sysop features for telemetry, command and control. Follow-on APRS satellites: http://aprs.org/sats.html Bob, WB4APR
---------- Forwarded message --------- From: ...space-track.org> Date: Tue, Nov 30, 2021 at 2:40 PM Subject: PCSAT Close Approach Notification
The United States 18th Space Control Squadron has identified a close approach between PCSAT (SCC #26931) and SCC #30230
Time of Closest Approach: 2021-335T02:20:51(UTC) Probability of Collision (Pc): 0.0003769653 Overall miss distance: 338.0m
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