deskthority

By the way... I noticed that both the "HP" PCB and the "Fluke" PCB have 4 soldering "holes" per key.
Considering that keyswitches only have two legs, that would be 2 holes too many... ?

Do you know the reason for the 4 holes ?
(maybe the capability to fit different kinds of switches ?)

Thank you Daniel !

Yes, the HP switch looks remarkably similar to the unidentified Fluke's one...
We're making good progress :)

I have added a few pictures to the flickr album.
Including a picture of the back of the PCB.
The pictures are a little blurry and it's not easy to see, but the "HP ...

Hello !
I’m trying to restore an "antique" HP keyboard.

The keyboard belongs to a desktop calculator from the 70s (HP 9825A). It is a little "tired" : sometimes two keystrokes are necessary to input one character, sometimes a single keystroke yields multiple characters, and the overall typing ...