Woodstock HP-27 ACT woes...

[jupiters_spot]

I'm curious how one goes about determining that the ACT is the root of the problem. I have exactly one HP-27 that's intermittent, so it's hard for me to measure known-good values and compare to my problematic calculator.

I do have a couple of HP-21 calculators, but from discussions on Panamatik.de it seems the CMOS technology differs on the 27, so again, not a good "apples-to-apples" comparison.