Thread: Zx81
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Old 23rd Apr 2020, 8:21 am   #281
John Earland
Join Date: May 2013
Location: Middlesbrough, North Yorkshire, UK.
Posts: 442
Default Re: Zx81

Hi, the socket is the ordinary type not the turned in one. The replacement ULA has very strong pins Ė in fact, it looks like they are already in a turned in pin Ďframeí, the type of connector that comes in strips where you can snap them into any length you want. No pins were bent and the IC is very securely seated.

I attach two photographs of the soldering from different angles. I have looked at them carefully and I really canít see that the soldering is incomplete but I may be missing something. Itís not terribly clear and even when youíre looking at it itís not clear but I think the soldering is sound.

The machine works perfectly with and without the RAM pack. I can save programs onto tape without the machine crashing. Itís the loading that is definitely the problem. Interestingly, I switched it on this morning, typed in LOAD and I got the stripey lines, and the machine didnít crash.However I didnít get the broader stripey lines you see when you are loading a program. After about half an hour this stopped completely and every time I typed in load the machine crashed. iíve now just left it for half an hour to cool down. And tried again and I get the screen in picture 3 but it wonít load.
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