Initial Gerbers / Mock Layout

A project log for HBKD-81

An open, replacement case design for a wedge style home computer

dave-collinsDave Collins 02/27/2023 at 06:030 Comments

A simple Idea, make a case for my orphaned ZX81.  If you have been following along with my little side project I have been restoring a ZX81 motherboard.  With that task mostly complete I now need a case to keep the little guy in.  searching the web I stumbled across this little gem over at the Timex/Sinclair web site :

The Suntronics KD-81.  WOW. I fell in love with this little thing, and its a big time on my want list but since searching for KD-81 keyboard on eBay landed me no results I guess I'm stuck with a reasonable facsimile.

I knocked this together over the last week and am currently working on getting it to production in order to test things out.  since the ZX81 keyboard is a fairly simple, well documented circuit I won't bore you with the details other than to say it uses MX style switches, has a power led and space for a current limiting resistor.  Additionally, we are using standard sized key caps, in the case that somebody wants to piece together salvaged key caps and go the sticker route.   The larger keys are half sized, SHIFT being a standard size of a ALT key, the ENTER key being the standard size of a tab or backslash "\" key.

 It might be a few weeks till I get all the bits and bobs together on this one, even though its meant to be cost effective, keyboards are still fairly expensive when made in a volume of 1.  The most expensive part being, shipping for anything we don't have to hand and switches.  I want to try to salvage as much as I can from existing tech if I can get it cheaper than just buying on the markets.