Non-invasive switch repair for Classic?

[Geoff Quickfall]

Whoa nelly!

The best way is to disassemble the entire calculator.

If not; using an eye dropper, drop some rubbing alcohol on the switch and then work the switch. HP Used a conductive silicon paste which turns into a great insulator over time. Once the switch is functional then introduce a small amount of DeOxit gold via eye dropper or can with the red straw.

The whole idea is not to splash solvent on to the facia plate (key surround).. Sometimes the lacquer finish is so degraded that even water will cause a white bloom.

Check this posting and scroll down to the pictures. It will show you how to remove a label then restore it to factory fresh non wrinkled form. Also discusses the switch problem.

Hp 45 restoration

And yes the book is being completed as we speak

Cheers.