Sinclair ZX80 / ZX81 / Z88 Forums

Humm just bought one of them off Ebay, Not managed to get it going (yet), there seems to be a problem with the clock oscillator, I have the 6.5MHz out of Q1 once I realized that the silk screen for the transistor was the wrong way round ! But it only produces a vmax of 1.6V, the signal out of pin 8 ...

Looking good there, I've just ordered one of his replica Jupiter Ace kits, hopefully once I have that working I'll be able to figure out what's wrong with my original JA board

Cheers.

Phill.

I was the original poster on the other forum :) So the ROM could be genuine, but is still overpriced seems to be the consensus. The RAM pack is genuine, I have one too, but I most certainly didn't pay £200 for it....IIRC it was more like in the 50p to a couple of quid range :) Mind that was in the e...

One thing I learned about computers way back when, is to always have at least one back-up copy... I'd go further than that and say the more disk surfaces* the data is on the better, even better if they are in physically distant locations. If there's something that can take out both home and work**,...

Wouldn't mind one of these too, if only to have a play with, can I collect in preson too, asuming you are coming to the RCM meet Andy ?

Cheers.

Phill.

A better way to do it might be to get something like one of the USB enabled AVR / ARM /PIC micro-controllers and code it to scan the ZX81 keyboard and produce proper PC codes.

Cheers.

Phill.

The lengths people will go to to save buying a replacement membrane :lol: Well to be fair I did something similar (de-soldered the molex connectors from the board and put them on lengths of ribbon cable, plugged into shortened membrain cable). However this was *BEFORE* the ZX81 membrains where avai...

1024MAK just beat me to it ;) Edge connectors are always a pain when it comes to dirt/tarnishing. The number of times I have to push and pull a NES, Super Nintendo, N64, Atari, etc... cartridge to get it to work ! And the design of the UK NES doesn't help that problem either, why they couldn't have...

sirmorris wrote:So who has access to a laser cutter?

Or a friendly Dalek ?

Cheers.

Phill.

Moggy wrote:

Prime wrote: It't basically an issue 1 motherboard with a DIY 32K addon, built into an old DELL keyboard.

unless it's a ts1000 then Issue 3 board surely?

Actually yes you are quite correct that is an issue 3

Cheers.

Phill.