Resistance is futile - Rejuvenating vintage computer keyboard key contacts

[Jeff_Birt]

In this video we take a look at a method to rejuvenate the keyboard key contacts on vintage computer keyboards that don’t work anymore due to having too high of a resistance.

This quest started nearly two years ago with an Amiga 500 that had a few nonworking keys. I tried many things that did not work on the Amiga key stems but found some of them did work for other keypads, like remote controls.

Bringing the Amiga and C64 stems back to life eluded me as they do not lend themselves any sort of conductive coatings. Due to their shape they flex, and the coating falls off. This started me on a journey to try to find out what caused the contacts to go bad in the first place and then to try to find a way to rejuvenate them.

After months of research I found a simple and inexpensive way to rejuvenate these high resistance key stems using common household chemicals. As a bonus I try out a new adhesive to fix the cracked plastic part of the stem.

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[Jope]

I've been a long time advocate of a simple piece of paper or even an envelope.

You push down on the key, give the rubber under it 4-5 good wipes with the copier paper, repeat for the other non typing keys and you're done. If you end up with paper dust on the rubbers, a quick blast of compressed air helps.

I just rejuvenated a C128 keyboard (same mech as the Mitsumi A500 kbd) that had maybe two working keys. First I wiped down the dust off the PCB but that didn't help. All of them started typing again after I did the paper trick on the rubbers.

No chemicals needed, no mess. Just a humble piece of paper from your printer or some old invoice that dropped down your mailbox is all you need.