开云体育

Can someone who knows about troubleshooting the SC502 please take a look at my 8 second screen capture video and offer opinions / suggestions.

This is the same SC505 I was working on a year ago!



Thanks!

Hi , Barry

It looks to me as though the vertical deflection is all off screen , up or down is hard to guess but what you are seeing appears to be just electron scatter from the bean hitting the top or bottom of the CRT envelope . Unfortunately my trouble shooting has been restricted to the storage circuits and not the vertical amplifier . You definitely need a copy of the service manual , which may well be on TekWiki . Power supplies are an obviouse thought here but as the horizontal seems ok it would need to be a local supply on the vertical amp . Another thought is possibly one of the deflection transistors . I cant remeber how easy or hard it is to get at the vertical amp components as its been a long time since I was inside mine but checking circuit balance from the input stage through to the deflection pins on the crt is likely necessary .
I hope this helps a little but it has been several years since working on mine .

Brian(UK)

When something that worked has been sitting for a long time it's a good idea to work over all of the controls while turned on - lots of times through all states. All switches, all pots, an so on. Ed

I have the service manual and have restored 2 of these SC502s. I have everything I need to work on these except the experience.

I appreciate the idea of a vertical amp issue as that was not obvious to me. Tomorrow I will look at that circuit!

Thank you!

Ed, I agree. I have been working on this SC502 for quite some time. This was the issue when I put It aside a year ago.

Thanks for the comment.