Thread: Zx81
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Old 15th Mar 2020, 8:44 am   #67
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 11,089
Default Re: Zx81

Originally Posted by John Earland View Post
when I plug in a 16k RAM pack the picture quality is significantly reduced on my lcd tv. Very grainy and stripey-Looks like an awful lot of interference. Maybe the mod will help!!
It may certainly be very revealing. If the picture is still not much improved after the mod and gets noticeably worse when you have a RAM pack plugged in that would suggest that there may be problems with the onboard PSU circuit, or, as others suggested earlier, the external mains PSU.

If the 'new' ZX81 also came with an original PSU, try running the 'old' ZX81 on the 'new' PSU to see if that makes any difference to your video quality.
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