HP-41cx Card Reader rebuild question

[Bruce Larrabee]

Win - I think you are right about the card wrap spring (hp's name for the part you refer to) not having any electrical connection etc. And I can't explain why it would cause the reader to come on and stay on.

My advice is to check the action of the switches with a meter (assuming you haven't done so) to make sure the are not becoming stuck on. They almost have to be. And it's an easy test to make.

I mean if it's a mechanical problem this should determine that. And if it is electronic then at least you can investigate that.

I'm having a hard time imagining that the card wrap spring is causing this but then I've seen stranger things.