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How do I get these Crts to display an Image?
(lemmy.ohaa.xyz)
I recently got a bunch of old 80's crts which I cant find any information about online.
I do have the service manual tho link
Looks like standart composite with external Horizontal and Vertical Sync to me but I'm not 100% sure and I dont want to fry anything
Thanks,
Oha
While I know(at least to some extend) what I'm doing, I still appreciate the warning. The Monitors.only interface seem to be these Pins labeled J1 in the Manual.
(I know, that brown discoloration looks horrible but it still generates high voltage and makes that high pitched crt whine)
Heres a picture of the entire Board in case that helps:
A3.2 and B2.1 in the manual show you the pinouts of that jack and the expected signal, unfortunately section 6.1 schematics and sec D timing diagrams seem to be missing. You’re going to need to find a suitable driver circuit. Without looking at the timing it might accept input from an old MDA adaptor or similar.
https://en.wikipedia.org/wiki/IBM_Monochrome_Display_Adapter
Edit: While this in behind a paywall it looks like this old article has a circuit for composite to TTL monochrome that would be what is needed.
https://www.elektormagazine.com/magazine/elektor-198812/47485
This one is from the 1980s itself and there also seem to be a lot of TTL to composite circuits out there that use fairly modern (and a lot fewer) components so with a bit of looking you might find a modern composite to TTL driver circuit. Look at the retro computer and retro arcade game forums, etc.
Forgot to reply but I got another scan of the manual that includes these scans from the person that gave me the crts. https://i.ohaa.xyz/raw/oRiMLv.pdf
Thanks, I really appreciate your detailed answer.