This is the wonderful I oscilloscope. I used for my senior project way back in 1990. Unfortunately, I can’t seem to find a trace on it anymore. I think it just needs some big capacitors replaced. Anyhow here is the operating and service manual included with the scope and I think it has schematics, but I’m not sure this would be a good project for someone who’s willing to replace the capacitors or whatever and troubleshoot that’s why I’m selling it so cheap $20 cash
I think I bought it for $149 from RadioShack but that’s in 1980s dollars which are worth a lot more lol lol