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Full Version: HP-41CV repair question
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I am embarrassed to ask this, but here goes. I have a nice 41CV (non-working) that I got off of TAS. I would like to convert it to a CL, mainly because the serial number is only different by 35 from my original 41CV (now a CL).

I can't get it to turn on, even after cleaning/swapping everything. I looked at the supply current while pressing different keys and found that the ON key doesn't cause the slight increase in current that I see with other keys. The key action itself is nice, but the ohmmeter says that the resistance when pressed is over 200 ohms. The other keys that I looked at are under 10 ohms when pressed. So, it makes some amount of sense that the machine can't be turned on. But is there anything I can do to fix the key, beside the obvious "remove the heat stakes and replace the dome"? I have never done this and expect that I'll screw it up the first time I try it. I have tried injecting some DeOxit into the hole under the dome but that doesn't seem to have done anything. Or should I stop wasting my time?

I should point out that my current measurement tests were done with a known-good CL board installed.
Hi Monte,

I usually pass some drops of Caig DeOxit with a pin through the hole in the keyboard board, and then "remove around" with the pin. Then some exertions on the key, then repeat again.

Sometimes works well, sometimes doesn't
If you have a card reader or wand you might want to see if they will turn the 41 on. I believe either trying to read barcode or a card will automatically turn on a 41. May be worth trying just to verify that the problem is with the on switch and otherwise the calculator is functioning correctly.
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