Thread: Zx81
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Old 19th Mar 2020, 11:17 pm   #104
John Earland
Join Date: May 2013
Location: Middlesbrough, North Yorkshire, UK.
Posts: 442
Default Re: Zx81

Thank you for that-I think I might need to replace the caps. I have noticed a couple of things now:

1. The ZX81 performs well at first but after a while the picture distorts (pictures attached)
2. After the distortion the computer switches itself off whenever you press a key. So for instance when I unplug and plug the psu back in I get the K display. When I press a key, Sat P, the picture goes blank and I either have to reboot or sometimes it resets itself.
3. Ive tried 3 different TVs-crt and 2 lcds -same issue
4. Ive tried two separate psus and with difference
5. The picture quality on the lcds is not as sharp as I would expect- the ZX Spectrum by contrast was very sharp. Same modification as on the ZX81.

This all occurs after the computer has been on for about 20 mins or so. I would appreciate any thoughts you might have.
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