HP-41C - Memory lost

[aurelio]

(02-01-2023 09:23 AM)Vintage63 Wrote:  I cleaned the battery pack contacts with a Dremel copper brush and cleaned the battery contacts with an earbud dipped in white spirit. I tried to tighten the screw a bit more but none of them budged so they should be ok, I guess.

Hi Marco!
Usually with broken posts issues, pressing the case, expecially in the upperside (it means near to the battery holder) you can notice the display changing. You can try to open the calculator, removing the four screws and checking with the help of a magnifier lens, the healt of your posts. At this point you can also check the quality of the contact between the CPU and the keyboard and the healt of the zebra connector. Of course opening the calculator is a risk...but also tightening several times the screws.