Looking for something I'm sure I've seen (25c)

[BobVA]

(06-08-2019 02:32 AM)[kby] Wrote:  Replacing the ACT didn’t change the symptoms. Found a disintegrating resistor, but replacing that didn’t change things either.

Power supply voltages are probably the next check, then. If the PSU is working it can be pulled down by a failed component elsewhere. (In this thread Alberto discusses needing to remove the RAM IC in his HP-25C before he could get correct voltages.)