Transit5-B5 (OPS 6582)
It is probably the oldest, still transmitting satellite in orbit.
NORAD-Nr. is 965
It is transmitting on 136.650 MHz, when in daylight
and reception is easy.
Launch date was 1964!
I definitely got something from the satellite today, though I have no idea what it is or what it is supposed to be. It is listed as FM narrow, though it looks very different on the waterfall.
I didn’t simulate the pass in gpredict or anything like that, but It was at 2 AM local time and the satellite was coming from North, so it sounds plausible.