HP 41 Card reader problem

[Geoff Quickfall]

Sounds like you have done this before.

I prefer the silicon tubing (military spec) with the hole in the middle. It simulates the pinch roller perfectly. The o-rings harden and I have to replace them on other people's 67 and 41s.

Using the current o-rings. I would move on to the circuit board solder joints. The card reader PCA is awkward to get to as you know. This flexes the solder joints and older brittle wires. Next the PCA to main PCA connections. Any obvious faults, do the circuits pass a simple continuity check.

I am away from home so a longer description will have to wait.

Geoff