Search found 3 matches

by vossi
Thu Mar 26, 2020 5:50 pm
Forum: Hardware
Topic: ZX81 repair help needed - strange fault!
Replies: 8
Views: 790

Re: ZX81 repair help needed - strange fault!

Thanks for the help.
I found the fault. The ULA-socket was bad.
Christian
by vossi
Thu Mar 26, 2020 12:59 pm
Forum: Hardware
Topic: ZX81 repair help needed - strange fault!
Replies: 8
Views: 790

Re: ZX81 repair help needed - strange fault!

Hi, I tested all chips in the working zx81. I stored the faulty zx81 about 3-4 years ago in working condition. I replaced at this time the old ULA to the new model 210E for a better picture. When I now powered on the zx81 the first times I was able to press a 0 or some other keys - all chars appear ...
by vossi
Thu Mar 26, 2020 8:05 am
Forum: Hardware
Topic: ZX81 repair help needed - strange fault!
Replies: 8
Views: 790

ZX81 repair help needed - strange fault!

Hello, I hope to get some help here - I normally repair Commodore or Atari - Sinclair is new for me ;) One of my two zx81 shows the "K" but the second pixel from right is a vertical line (white because of the reverse K). If I press any button I get these verical stripe over the whole screen and they...