I have an HP-65 that I refurbished a few yars ago (new drive roller, clutch, cleaned head & leaf switches, etc. and well lubed).
It was working perfectly until today. I can read cards fine. I can write cards and then read them back in and get a steady "0.00".
However, when I switch to W/PRGM, in addition to the normal keycode display, I see minus signs at the left and right ends of the display. And the program does not run properly, the display just flickers dimly. This strange behavior only happens with cards that I have recently written to. Standard Pac cards, and cards I recorded a month ago read and run properly and don't display the minus signs.
AFAIK, the most likely culprit with write failures is the leaf switches. But I have not read any mention of the strange display. Could the switches be "marginal" - making intermittent contanct (somehow getting out of adjustment by just sitting on a shelf)? or maybe some electronics are finally dying (caps, coils, etc.)
Anyone seen this before?
-John (3665)