Only identified issues were some corrosion on the bottom right of the Z80 and surrounding caps which I’ve cleaned and reflowed, and the 270pf cap below the cartridge port was smashed and has been replaced.
Following the service manual I’ve confirmed the 7805 is outputting a clean 5V and the 3 clock points all have frequencies within the set ranges but the next test says check JR point for rising voltage (to 3.7V) but I cannot find that point. The two components mention that might be faulty if the voltage isn’t correct (a resistor and a capacitor) both test okay, with 5V supplied to them.
Anyone got anything else I can test, even where I can hook up a logic probe and what I would be looking for?
submitted by /u/UniqueCSX
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