Where is NOP on the HP-67 ?

[teenix]

(01-10-2021 10:23 PM)albertofenini Wrote:  Just a quick update
It has to be a cold joint of some sort
When we took the keyboard pcb out of the shell and we connected everything to start the tests the 10th digit started to lit correctly
Depending on how much torque we apply on the upper left screw it doesn’t lit
We’ll post soon pictures in the original thread
Thanks for all the help !

I'd try to re-solder all the cathode driver and faulty display module pins. No need to remove old solder first.

If that fails, it could be a hairline crack on a circuit board track.

cheers

Tony