Regarding HP 8920A problems where the diagnostics report "Squelch Fixed High Level and Squelch Open High Level" fail, this was because of a failure of Q512 in the receiver module. This failure mainly occurred with earlier receiver module numbers 08920-61028, not the newer receiver - 08920-61102. Q512 is a BFT-93 leadless transistor. With this failure, you usually see a 10 - 15 dB drop in receiver sensitivity. Good luck!? rick
