HP 2623A Keyboard

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OldIsNew

02 Sep 2017, 10:08

I like older terminal boards for a couple of reasons: 1)They're cool looking, 2)They're generally relatively cheap. This is an HP 2623A terminal board.
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Hi-Tek (or Stackpole?) modular switches
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switch_bar.jpg
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Went ahead and traced it out and wired it up
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Typing on it now. Not my favorite switches for sure, but it's still kind of a fun board.
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Daniel Beardsmore

02 Sep 2017, 13:15

I use "modular" to refer to the patented dovetail system where the switch blocks can be physically connected. Stackpole also came up with a simpler design, that you can see (but not in use) in the [wiki]Lear Siegler ADM 11[/wiki] keyboard.

The HP2623A switches are indeed Stackpole yellow, but the contact design is the one that I associate with Hi-Tek. That proves nothing as we don't know how similar the two products were when it went to court. Since the court case failed, my feeling is that Stackpole's design already was different enough to not justify a claim of patent violation, but we don't yet know.

See, yours is extremely similar to the [wiki]Intel iPDS[/wiki] keyboard, including the whole space bar assembly — the switch contacts are pretty much the only difference! Even the stepped ends to the separate bars are present.

Can the keyboard be dated from the ICs? If this is Stackpole, it must be fairly old.

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Daniel Beardsmore

02 Sep 2017, 16:50

There's a new theory from two former Hi-Tek employees (D'Milo and Susan) — that all Hi-Tek sliders were white (colourless). So that would imply that Stackpole did copy the exact contact design originally. And funnily enough, every confirmed Hi-Tek high-profile keyboard listed on the wiki has white sliders …

D'Milo suggests that this one may be a mixture: Stackpole for the main keys, and Hi-Tek for the top rows.

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Sangdrax

02 Sep 2017, 20:29

Looks great. How did you hook it up? Just rows and columns to a teensy?

I've also been meaning to ask this from all the stackpole and hi-tek switches like this you see on stuff like the old TI home computers. Does lube on the stem help at all with the feel?

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OldIsNew

02 Sep 2017, 21:37

Daniel Beardsmore wrote: Can the keyboard be dated from the ICs? If this is Stackpole, it must be fairly old.
Forgot to mention the date, the inside of the case is stamped Aug 12 1984.
Sangdrax wrote: Looks great. How did you hook it up? Just rows and columns to a teensy?
Yes! Just took a little time to figure out the matrix, but nothing complicated. Just wires from the IC pads to the Teensy.
Sangdrax wrote: I've also been meaning to ask this from all the stackpole and hi-tek switches like this you see on stuff like the old TI home computers. Does lube on the stem help at all with the feel?
I was wondering about that too. The switches on this board were pretty clean and feel ok, but I would imagine these type switches could get rather scratchy. Has anyone tried lubing them?

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Daniel Beardsmore

03 Sep 2017, 01:24

What do the white switches look like?

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OldIsNew

03 Sep 2017, 08:32

Daniel Beardsmore wrote: What do the white switches look like?


Here are some better pics of the white and yellow switches:

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yellow_switches.jpg
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Daniel Beardsmore

03 Sep 2017, 16:21

Interesting — they're different in so many ways. Even the contacts are a different shape. It would seem to be Hi-Tek white switches and Stackpole yellow switches. Still under investigation!

ak15199

01 Apr 2023, 06:38

I've just reverse engineered the wiring on one like this, but with the extra decals on the number pad. The connectors look like this, just in case anyone finds this useful in the future!
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