Posts: 252
Threads: 14
Joined: Jan 1970
Tal,
Hmmm, that's odd. I never actually traced the circuit of an HP-34C but in other continuous memory machines, the CMOS memory is powered directly from the battery pack (with a capacitor as a backup), independent of the DC-DC converter power supply that powers the rest of the machine. So if the continuous memory receives power at all, its contents should survive power cycling.
Unless... I don't know the algorithm the HP-34C uses to verify whether the memory contents are valid, but I can imagine that if there is a failed bit in its memory, it may read the contents as invalid every time it's turned on. But I think I better stop speculating now and perhaps let others who know this machine better take over...
Viktor