Re: Sinclair ZX81
Hello All,
I have used my old scope to make the tests below. Scope set to DC.
1. Pin 16 ULA
(a) volts/cm=0.5
(b)Time/cm=2ms
2. Output of one transistor comp video adaption(no signal diodes)
Same settings as above.
Used merlinmaxwell's method to check clock on pin 6 of cpu. Reading on AVO8 was 2.5V so clock might be working.
I have attached the traces for 1. and 2. above.
You will realise how little I know about this stuff based on my question. Do the traces in 1. and 2. above look as you would expect if the ula was working?
Regards,
Ken.
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