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Woodstock Keyboard Designs
01-22-2015, 03:47 PM (This post was last modified: 01-22-2015 03:49 PM by PANAMATIK.)
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RE: Woodstock Keyboard Designs
(01-19-2015 03:30 AM)aj04062 Wrote:  Does anyone know when in 76 HP switched from metal strip keyboard contacts to plastic membrane?

I cannot answer your question. But I have some other keyboards with different dates printed on it. Perhaps this can give you some information. Others don't show any date.

And I know that the keyboard rows and columns were routed differently on the main board to the ACT processor pins in HP-21 and HP-25, so they behave different, HP-22/HP-25C has the same layout as HP-25. The membrane style keyboard in the third picture I found in two of my HP-29Cs.

I have even more (different date) keyboards, but couldn't add all images as attachment.

                   
Bernhard
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Messages In This Thread
Woodstock Keyboard Designs - aj04062 - 01-19-2015, 03:30 AM
RE: Woodstock Keyboard Designs - PANAMATIK - 01-22-2015 03:47 PM
RE: Woodstock Keyboard Designs - aj04062 - 01-22-2015, 05:03 PM
RE: Woodstock Keyboard Designs - aj04062 - 01-24-2015, 07:27 PM
RE: Woodstock Keyboard Designs - aj04062 - 01-28-2015, 01:47 PM



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