Weird behavior HP41c

[Geoff Quickfall]

Both shorting the extreme left to the extreme right battery contacts and the inverted batteries should induce Memory Lost.

Forget the inverted battery method .

I have in extreme cases left the batteries out of the calc for a week with a shorting clip attached to both battery connections mentioned above.

Your two PS's change the diagnosis. It now sounds like a RAM problem. Maybe a loose solder connection on one of the ram chips.

Caveat, the hex nuts were not made to come off and go back on. They self tap and end up cross threading the next time they are used. HP when repairing used spacers in place of the hex nuts.
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