Hi there, just a status on my CBM 720 repair - and maybe you can help as well :-) After replacing some capacitors in the original power supply, I checked the first logic signals and found /RES continuously low. Traced it back to a 556 timer chip with a broken output. Replaced it, and found from scope traces that the CPU was working. Unfortunately after a few minutes the old power supply went south with a small "plop"... I decided to not get further with it, and instead replace it with a PC power supply. That worked well, and got some video output after adjusting the screen brightness with the small knob on the back (I found video signals with the scope, and then decided to check that knob, which in fact ... :-) Unfortunately it's not yet fully working, but much further. The CRTC gets initialized, so that means the video output is working, the CPU as well (at least to a considerable extent), but other stuff is still broken. Anyone knows the video pattern shown here? https://www.flickr.com/photos/afachat/sets/72157647798386959/ Thanks André Message was sent through the cbm-hackers mailing listReceived on 2014-10-19 20:00:02
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