UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Non-working Commodore PET 3016

SiriusHardware · 7th Jan 2021, 8:27 pm

Yes, that might be progress of a sort. If Colin could manage to desolder and disconnect pin 7 of UG5 from its associated pads and through-hole then we could see whether UG5 is the source of the short / is working when disconnected from the short.

If we eventually get to the point of suspecting that one of the eight, no, nine ICs soldered to the CLK1 line is faulty then I would probably choose UG5 to rule out first, as the output on pin 7 is driving the inputs of all the other ICs connected to that CLK1 line. I think Mark suggested much the same thing.

Colin, you haven't really said what you have in the way of desoldering gear, if any?

7th Jan 2021, 8:27 pm	#67
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,558	Re: Non-working Commodore PET 3016 Yes, that might be progress of a sort. If Colin could manage to desolder and disconnect pin 7 of UG5 from its associated pads and through-hole then we could see whether UG5 is the source of the short / is working when disconnected from the short. If we eventually get to the point of suspecting that one of the eight, no, nine ICs soldered to the CLK1 line is faulty then I would probably choose UG5 to rule out first, as the output on pin 7 is driving the inputs of all the other ICs connected to that CLK1 line. I think Mark suggested much the same thing. Colin, you haven't really said what you have in the way of desoldering gear, if any?