RCA CTC-11 Restoration

[wcarroll]

Well, the chassis is back in the cabinet and working quite well. See attached pic of "The King" in color and also another pic of Paul Simon. All of the adjustments on this set were way off... I now have a dot / crosshatch generator so I've been stepping through the convergence and purity settings and now have a decent picture. I couldn't quite finish since the right of screen convergence settings require one of those hex-shaped plastic adjusting tools (I've got one somewhere around here..... ) I'm sure I'll need to run through the whole process again since each adjustment seems to affect the earlier adjustments.

I did notice the red color dropped out a couple of times... It was not an instant drop out, but more like a gradual fade out. And then would come back. Since adjusting the kine bias and red, green and blue pots it hasn't happened again. Anybody have any ideas on what could cause this?

I am using a DVD player as my program source. Some of the DVD's cause interference in the upper left corner of the picture. Is this some kind of copy guard signal? Is there some way to filter this stuff out?

Also had quite a challenge getting the vertical linearity set. It was way off to begin with and took a bit of trial and error with the height and linearity controls to find a good combination. Still not perfect, but much better now. Pretty neat how they hid these settings behind the contrast and tone knobs!

[Phil Nelson]

Yee-hah! Definitely looks like progress.

Phil

P.S. Any time you want to trade your cabinet for my scarred semi-knob-free piece of junk, just give me a holler :-)

[blue_lateral]

Originally Posted by wcarroll

I am using a DVD player as my program source. Some of the DVD's cause interference in the upper left corner of the picture. Is this some kind of copy guard signal? Is there some way to filter this stuff out?

Since the interference is added by the player on playback, the best way is to get a DVD player that has been modified not to add it.

http://audiokarma.org/forums/showthread.php?t=54696

John

[wcarroll]

Still having a problem with the RED color fading in and out... I'm not sure where to start troubleshooting for this problem. The picture is great when the red is working. Then it just slowly fades out until there is no red at all. Sometimes it will eventually come back, other times it takes messing with the red, green, blue and bias pots on the back. The crt hasn't been tested. Should this be my next step? I'm not sure what the signs of a weak red gun are? Seems to me that if there was a problem with the red gun, that it would always be bad.... not fade in and out. Maybe something in the color demodulator section?