A heated "discussion" between JL and JT prompted me to post this. I often
get these HP 8116A generators in for repair that have processor reset
problems. CR3 and CR4 in the reset circuit become leaky which pull the
LM324 input negative and seems to drive the LM324 outputs into unexpected
states. On a power up the voltage at CR3 and CR4 swings from about +15 to
-15V or so. They are driven positive first by a LM348 through a diode,
then pulled down through a 100K resistor to -15V. See the two jpgs I
posted for the schematic. My questions are 1. Is it expected that the
slightly negative voltage at the input would do this? and 2. Is there a
reason why CR3 and CR4 fail so often? The diodes are 1N4150. Obviously
there isn't much current flowing through the diodes... Maybe there was a
bad bunch of parts?

Thanks.