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Switch identification on an old calculator

Posted: 24 Mar 2020, 06:42
by stoddartc1
Hey all, I found an old calculator and I was just wondering if anybody could identify the switches it uses?
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It's an Olympia CD401A (not the Nixie tube model unfortunately).
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The return force is driven by an external coil spring, and there appears to be an o-ring to dampen the sound. The switches are extremely smooth which I why I was curious as to what it uses, as an entire keyboard decked out with them would be awesome!

Any help is appreciated

Picture of internals:
OlympiaCD401A_2.jpg
OlympiaCD401A_2.jpg (63.31 KiB) Viewed 1881 times
Source for that picture:
http://www.vintagecalculators.com/html/ ... brary.html
Other helpful sources:
http://www.calcuseum.com/SCRAPBOOK/BONUS/16606/1.htm

Re: Switch identification on an old calculator

Posted: 24 Mar 2020, 14:23
by Anakey
hmm the keycap mount along using the external coil spring would suggest to me that it is some form of foam and foil switch however without seeing the back of the keyboard pcb there is no way to be sure

Re: Switch identification on an old calculator

Posted: 24 Mar 2020, 16:09
by kelvinhall05
Anakey wrote: 24 Mar 2020, 14:23 hmm the keycap mount along using the external coil spring would suggest to me that it is some form of foam and foil switch however without seeing the back of the keyboard pcb there is no way to be sure
I bet it's foam and foil. I think you're right.

Re: Switch identification on an old calculator

Posted: 23 Jun 2021, 00:40
by soyuz
necro - this is alps spring bridge