Hall-effect keyboard query / was Re: Sources for 8b TTLkeyboards (Keytronics)

Brent Hilpert hilpert at cs.ubc.ca
Fri Dec 5 00:21:36 CST 2008


Chuck Guzis wrote:
> 
> On 4 Dec 2008 at 20:08, Brent Hilpert wrote:
> 
> > With all this talk of old keyboards, I figured it was time to pull out one that
> > I've had kicking around for awhile but hadn't assessed as yet. It's a
> > very-ASCII keyboard (control codes are labeled on the keys) using Hall-effect keyswitches:
> >   MICRO SWITCH
> >   Freeport, Illinois
> >   61SW12-2
> >   SW-10405
> >   date-stamp: 75/49 (1975)
> > (Would the MICRO SWITCH indicate this was from Honeywell?)
> 
> I don't know that Honeywell tinkered much with the Freeport operation
> in 1975.  I've got a couple of keyboards similar to yours from 1977,
> but with different encoder IC's (outputs something like "scan
> codes").  A lot of the encoders of the time were custom mask-
> programmed items.
> 
> Micro Switch made keyboards for a *lot* of firms.

Put another way, was Micro Switch (the company) a spin-off or subsidiary of
Honeywell? Some web references seem to imply an association in the development
of integrated Hall-effect sensors in the late-60s with Honeywell, but there is
some confusion in there regarding Honeywell and their earlier (1940s)
development of simple mechanical microswitches.
(I'm just not familiar with Micro Switch as a company.)



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