RCA 21-S-510N Restoration Thread

[Hcompton79]

Update:

I replaced all of the paper and electrolytic capacitors and while I now have wonderful sound, I've lost the raster. I noticed that the HV rectifier was not running, so I did some checks to make sure the flyback wasn't shorted out and it wasn't. So I pulled the horizontal output tube cap off and used an insulated screwdriver grounded to chassis to try and draw a spark off the cap which I could not do, I believe this means no RF is going to this tube, correct?
what should I do now?

[Hcompton79]

Also, I noticed a slight blue-violet glow in some of the tubes, is this normal?

[dieseljeep]

Originally Posted by Hcompton79

Update:

I replaced all of the paper and electrolytic capacitors and while I now have wonderful sound, I've lost the raster. I noticed that the HV rectifier was not running, so I did some checks to make sure the flyback wasn't shorted out and it wasn't. So I pulled the horizontal output tube cap off and used an insulated screwdriver grounded to chassis to try and draw a spark off the cap which I could not do, I believe this means no RF is going to this tube, correct?
what should I do now?

Don't touch the horiz output plate to ground. It draws too much current and can damage the flyback and the horiz output tube.
The HV supply circuit is protected by the 4/10 amp fuse, the only one in the set.
If the horiz output tube isn't getting drive, the tube will red-plate.

[Hcompton79]

Ah ha! I found the problem , I accidentally wired a 0.01 uF capacitor across the wrong leads of the horizontal output tube, we now have HV. However, the screen now lacks a full raster only the middle of the screen shows a raster and the audio has dropped out.

[dieseljeep]

Originally Posted by Hcompton79

Ah ha! I found the problem , I accidentally wired a 0.01 uF capacitor across the wrong leads of the horizontal output tube, we now have HV. However, the screen now lacks a full raster only the middle of the screen shows a raster and the audio has dropped out.

You have to restore a TV in stages.
First, you have to determine, what does the set do?
I worked on the very same set, about six months ago. There was a laundry-list of problems.
First, the volume-contrast control was bashed in. Remove the control and reassemble. Was lucky it could be repaired. Try the set again and naturally the horizontal frequency was way off, but you could tune in an image, that was a way off and reasonable sound.
Then the vertical circuit needed recapping.
I worked on these sets when they were faily new. The same problems as today, sixty years later.