I'v been a couple of days working my CBM 3032 repairs. I started with this junk board:
And left it in this state:
There are a couple sockets more, but the output does not change. I have configured the jumpers as the technical manual states and replaced every EPROM with its original BASIC 2 from Commodore (NOS).
The 6502 has been tested and is working, her only PIA has been replaced (missing pins) and the second one has been added. Some components like the '154 or the 555 have also been replaced because they were prey of rust.
After testing a few times the result is this one.
I'm also having no DOUT at the U256:
And CAS fixed at high-level.
I've tested some ICs regarding CAS and seem to be working... so I don't know what could be the issue.
About the video circuit I'm sure there is a failure too, because those "junk" values should fill the screen completely but they do only occupy 2 1/2 lines in the middle of the screen.
I am not sure about what should check now. There's no expertise in any system of the PET/CBM line in Spain as their sales were poor (and that's being generous). There are only a few of them, most in universities or in hands of speculators, some of them being offered for no less than 800€ or even in the range of 2k-3k€. For this reason I thought this is the best place to come for some help with this system.
Just some background... This unit is nicknamed "The International" not without a good reason. Its case, PSU and monitor came from UK in a single block. Its BASIC 2, Kernal and Editor ROMs came from the same source. The keyboard came from Germany in a three units pack (all of them incomplete but I was able to build a working and complete one from pieces from the two 2001N, the other was one from a B model). The PIAs came from the UK too, but from a different source. After three years we found its board, which came from Italy but had memories manufactured at DDR. The character ROM was from the only Andorran PET, which is working but has some strange video problems. In other words it came from all around Europe.