Sinclair ZX80 / ZX81 / Z88 Forums

Hi, Yes, the Recom or Traco are the ones I had in mind. So pictures of people adding a small heatsink to the ULA is, be polite, "stupid". OK, lets skip that one, makes it more easy... I also saw some replacing the sockets with gold plated, but indeed lets first try IPA. If that works, why fussing ar...

But I thought that ULA mainly fails because gets too hot?

But both flat cables look really bad. Will need new keyboards...

:P :P :P Me happy, based on the scope readings both devices should work. I also see a video signal, although not sure if ok. So I really need to get composite out now. Ok if I do the simple bridge of the ULA output? At least I should see something... Now, my most important question: if both ULA’s wo...

Ok, At least I see power on the board and 5v on pin40 of ULA. Hoped there was a power issue, but no luck... Suppose better get my scope once for next analyse. Hopefully soon as quite busy with other stuff. Sorry... :( :( PS: as I get no image at all, could this also be related to ULA? Or should I se...

Hi all, Pulled 2 ZX81 from a cabinet. They are not originally mine. 1 (only the unit) I got from a school cleanup, claimed it doesn’t work. Another one, unit, power supply and 16K, I bought a long time ago from EBay for low price, so almost sure also has issues. But never really had time to look int...

Compositie signal from my WII works fine on the first TV. Weird it has problems with the Spectrum.
Perhaps better install a composite module than the current wire bridge....

Hi guys,

Yep,
Root cause was the TV. Another one provides a nice screen.
Found out 2 columns of keys not working. Will need to check flatcables...

Thanks,

Good idea to see the impact of changing paper color.
Will also try on another screen and see the outcome

Hi all,

In attachment 2 screenshots. Not so easy to take a good picture.
Not sure if this is normal but screen also look very blue. I expected white (or close to that)