CTC 21 goin green

[RCAkid]

I have a CTC-21 that I am about to begin the restoration process on. The good news is that I have a pretty clear picture so we have IF, HV, Audio, some color sync and virtually every circuit is working.

Now, in trying to establish what all is going on with the chassis, I am currently unable to attain a red raster/screen. After checking purity, the best I can accomplish is a reddish/brown sepia tone picture when the red screen control is full on and the blue & green are turned all the way down. I have had this CRT/yoke combination working and converged properly and tested with at CTC-38 chassis. So I know the purity and yoke are working properly.

Green seems to be the dominate color and until the set warms up, green overrides even the blue. Amazingly I can attain a near b/w picture but only if the red screen control is on full, the green down all the way and the blue added in a bit.

At this point, I can get some color sync, blues, yellows, greens but no red for facial tones. By adjusting the tint control, flesh tones are either green or blue.

Now knowing how squirrely 6gh8a tubes are, I replaced the two on the chroma board with known good replacements. No change. I changed the
6jc6 as well with no change.

Basically, I am really missing red. I have not re-soldered the pc board chassis grounds yet and that may well be the problem. I know that is a must do for all pc boards in this type of chassis.

I also suspect that the caps in the power supply are weak or there are resistors that are off as when I turn the green screen control to max or turn the brightness control to max, the picture goes out of focus and shrinks a bit horizontally.

Also, there seems to be some vertical issues. While there is no rollover and the screen is filled out properly, it annoyingly expands vertcally, just a little bit and shrinks just a little bit rapidly almost as if someone were playing with the linearity controls just a tiny bit. The screen has full raster/picture while this is occurring. I do notice some of the shields on the IF tubes are missing and I will have to find replacements.

So, with all that said, any thoughts on where on the chroma board and what components I need to be looking at to correct this problem?

I have a similar issue with at CTC-16 but I am able to get a red raster. Just green tries to be the dominant color, especially when there is no signal (green snow instead of white snow). Any thoughts on this issue would be appreciated too.

I know this is a long thread but I figure the more info I can post, the better the educated guessing.

I realize this is a complicated chassis and this is my first color set restoration. Since I grew up with this set, I figure it is the best one to restore first as I know this chassis best.

Thanks to all for your help.