In search of 4B3A Microswitch Keyswitches (for a restoration, not a keyboard collector!)

Ian Finder ian.finder at
Fri Jul 10 13:27:30 CDT 2020

Yeah Al, that's a great suggestion. I was looking at the AH1815 last night.
The challenge is getting the whole assembly as thin as the original, which
presents a not insignificant challenge-

Even using the SOT553 package of this: - I'd have to do some
trickery, like have it mount into a hole into the center of the board.

On Fri, Jul 10, 2020 at 11:06 AM Al Kossow via cctalk <cctalk at>

> On 7/10/20 9:45 AM, Al Kossow via cctalk wrote:
> > 4B3A is a non-multiplexed contact closure type which is extremely
> difficult to find.
> Since it isn't very fancy, I wonder if you could make a new board with a
> modern Hall
> effect sensor? You just need a contact closure.

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