I’ve always liked using the Cherry MX Green switches in my keyboard projects for other machines (TRS80 M4 Keyboard Replacement).
Is there a keyboard replacement project for the Heathkit H89? I have yet to get in my H89 and am not sure. I was thinking it was already mechanical? I don’t remember.
For other retro computers (C64, TRS80 M3/4, etc,), the biggest problem has been the making and printing of the keycaps.
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So, yes, there is a keyboard replacement project for the H89. This work was led by our own Terry Smedley, who did his usual excellent job. There is good documentation but I’m not sure it’s been pulled together and posted to share. I plan to write this up but haven’t made it a priority. I’ll try to bump it up.
https://photos.app.goo.gl/9ZPjusAamgPg4NQ69
Todd has the boards but if you can wait for some more documentation it may save you some time and having to re-learn mistakes.
I should point out that Terry also did Cherry replacements for the H8 front panel
https://photos.app.goo.gl/J27bQeSo9NVavZac9
and even the H9!
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I don’t think anyone is making the older (Stackpole) switch keycaps. The picture you sent was from some time ago. You could always try 3-D printing some.
The new Cherry keys (in my pictures) use keycaps from Maxkeyboard.
The H9 is a cool artifact but it is truly a “dumb” terminal. It is all 74xx series chips (no microprocessor) – basically like Don Lancaster’s TV Typewriter. Its fun to show at VCF events and has the classic H8/H10/H11 styling. In its base model it’s limited to 12 lines of 80 characters, all upper case. The keyboard replicates a teletype. There were mods to add lower case and double the number of lines. It is effectively limited to 600 BAUD (can communicate at higher BAUD rates but the display logic slows things down). The “plot” mode is fun to demo. It can also split the screen into four columns 20 bytes wide (this was supposedly for viewing short line code like assembler source (presumably uncommented!)
I’m not aware of any good videos on the H9. Perhaps Jeff will do one if he gets an H9 some day… 😊
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Sure, not hurry, but wow, those are cool keyboards.
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