Dumont RA-109A help needed - very little high voltage

[kramden66]

Wow hope you feel better soon , i don't have a tick tick i have a rappid sound that causes the image to get in and out of focus and slight chage in brightness and it jitters the image , you can see on the probe the voltage drops and rises , so whatever it is it has moments where it slows and almost stops or just keeps going , i can try replacing the doorknobs again , i have ceramic disc caps that are 470pf at 15kv , i tried them before but that was when the lead was being shorted , now that it is not maybe they are the cause.... btw it looks like i will only have to do a little touch up on the vertical , looks close and the horz might be ok , once i lick this issue it wont require extensive linerty / width issues.. i hope.

mike

[old_coot88]

Originally Posted by kramden66

...i don't have a tick tick i have a rappid sound that causes the image to get in and out of focus and slight chage in brightness and it jitters the image..
mike

What you describe sounds like one of the leads going into the CRT socket is broken loose from the lug. Have you checked there? Or maybe one of the lugs is not making contact with the CRT pin.

[ggregg]

My RA-109 had a similar issue. It was coming out of the doubler circuit. Cleaning eliminated the issue, for now anyway. It was up by the caps things that attach to the top of the tubes. Carbon traces, I assume.