Sinclair ZX80 / ZX81 / Z88 Forums

Thanks for your suggestions msknight. I've been reading up on this and it looks like some kind of ffc or fpc flat cable with a 2.4mm pitch should work with the Molex connectors but I haven't had any luck tracking them down - they all seem to be 0.5 or 1mm. I'm thinking a Plan B might be in order :lo...

Hi all I've built myself a mechanical keyboard using a ZX81+38 PCB which I've been using with various ZX81 and Spectrum emulators via an Arduino Leonardo, which is great. I'd like to solder a set of the 5 way and 8 way membrane keyboard connectors onto the mechanical keyboard PCB and then use some k...

Good point, thanks Mark.

Thank you all for your thoughts - some mixed views, a bit like my own mixed feelings :lol: It's a peculiar bit of computing history really, I don't suppose Apple, Dell or Lenovo would let a product out of their factories looking like that nowadays :o Maybe I'll just do the composite mod so that it c...

Hi all So I bought another zeddy as spares/repairs on Ebay for a bit of tinkering with the intention of adding a composite mod and internal 16K RAM upgrade. However, when I opened it up to take a look I found that it was an early version with the stand-off board on the Z80 to rectify a ROM error as ...

Thanks for the info. I'll order the parts and make one up myself.

Dave

Hi all

I gather that it's possible to use a ZX81 with a Spectrum PSU using a conversion cable. Does anyone know where I could get one, or how easy it would be to make my own?

Thanks

Dave

Before I make my second post, I though I'd better do a quick intro. My first computer was a ZX81 with 16K RAM back about 1983, moved on to a Spectrum then MSX and Atari ST before getting a PCs. I've been using Raspberry Pi's and Arduinos for the last couple of years and dabbling with Python and this...

Hi Mark The Traco was added because the 7805 wasn't working, the capacitors haven't been changed. I'm getting the same readings whether the RAM pack is fitted or not: 12.02v at power connector and Traco input 5.02v at Tracto out, on ULA, ROM, Z80 and the 1K RAM chip. Also 5.02v power to the composit...

It's got a Traco Power TSR-1-2450 instead of the 7805. Might that make a difference?