Re: Gemini 80-Bus System
First thing to check is the reset circuit - look at voltage across C44. Also then short out C44 and then release the short and see if it starts behaving.
Reset circuits like this can be sensitive to power supply rise time as well as leaky capacitors (Which age).
Next step would depend on what test equipment I have available. I would also disassemble the first bit of the program rom - that would give you some understanding.
PS - the circuit diagram does not appear to be posted.....
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