CTC-4 Director 21

[old_tv_nut]

I don't have the SAMS, just the schematic that's on earlytv.org (RCA?). If "L86" on SAMS is the output of the 3.58 MC oscillator (T115 on the earlytv schematic), then you may be killing the oscillator when tuning too far. If all the bars suddenly go to the same greenish hue, that can be an indication that the oscillator stopped running on some chassis (I'm not certain about the CTC4).

Edit: we crossed posts - glad you have it working.

[old_tv_nut]

I really don't have a firm idea about the interference, but I see what looks like delay line ringing in the video (multiple trailing ghosts). Maybe there could be a bad ground or something that's making the video circuits oscillate (?). Does the interference change when you adjust the contrast?

[SwizzyMan]

Well I found the source of all the nasty interference. It was my agile modulator! Funny thing is that the interference doesnt really show up in my 7 but does show up a bit in my 5. I hooked the set directly to my cable box and the difference is night and day. Obviously purity and convergence are piss poor, but I'll do convergence later tonight.

[SwizzyMan]

Convergence on this set couldnt be more confusing. Has anyone here done convergence on a 4 and could you guide me in the right direction? I tried to follow the manual, but it is still rather confusing.

[BigDavesTV]

Wow, nice to see it at this point, congratulations!

[Phil Nelson]

Originally Posted by SwizzyMan

Convergence on this set couldnt be more confusing. Has anyone here done convergence on a 4 and could you guide me in the right direction? I tried to follow the manual, but it is still rather confusing.

Your TV is starting to look pretty good. What manual are you using? The most detailed service book is the 91-page RCA service clinic manual. This article has a link to download it:

https://antiqueradio.org/RCACTC-4ColorTelevision.htm

I believe the color setup procedure starts around page 25. Go through it step by step, in the order given (i.e., purity first, then convergence). It's essential to use a pattern generator. The dot pattern is most useful for convergence.

Regards,

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

[SwizzyMan]

Thanks for the kind words guys! The set is really shaping up now. But there is still a lot of work to be done both electrically and on the cabinet. Im having custom decals made for the decals located under the knobs. Im debating on whether to refinish it or not. Oh and Phil, I am using the factory RCA manual to go through the setup. I will take a look at the one on your page too. Convergence needs to be done before I can do purity since poor center convergence will make it hard to get good purity. Ill try and figure out convergence soon, but it sure is confusing!

[benman94]

Try another modulator. I've found direct connection to a Charter cable box (that's who we had out by my folks) to overload the set. I'm wondering if you don't have an AGC issue, or if the Blonder-Tongue wasn't set too high....

[Electronic M]

Originally Posted by SwizzyMan

Thanks for the kind words guys! The set is really shaping up now. But there is still a lot of work to be done both electrically and on the cabinet. Im having custom decals made for the decals located under the knobs. Im debating on whether to refinish it or not. Oh and Phil, I am using the factory RCA manual to go through the setup. I will take a look at the one on your page too. Convergence needs to be done before I can do purity since poor center convergence will make it hard to get good purity. Ill try and figure out convergence soon, but it sure is confusing!

As soon as you do purity it may throw dynamic and or static convergence off and to an extent vice versa....This will probably be an iterative process, touch up purity, touch up static convergence, rinse and repeat till it is right.

It may be wise to unplug the convergence yoke do the static and purtiy till right then plug it back in and go after the dynamic.....Make sure your H and V size and lin are right before doing the convergence since there will be interplay.

[Steve D.]

You'll probably be able to achieve good center convergence eventually. Edge convergence, in my experience, may be a little more difficult. If the picture looks good from 7 or 10 feet away and you've been dealing w/the convergence for hours...
Just know when to walk away. Or order up a strait jacket to restrain you from tweaking one more control.

-Steve D.

[WISCOJIM]

Originally Posted by Steve D.

Or order up a strait jacket to restrain you from twicking one more control.

-Steve D.

Yikes is right! http://www.urbandictionary.com/define.php?term=twicking

[Steve D.]

Originally Posted by WISCOJIM

Yikes is right! http://www.urbandictionary.com/define.php?term=twicking

Alas, My spellcheck let me down. Who knew?
My post has been corrected.


-Steve D.

[SwizzyMan]

This thing keeps getting better and better! I was able to get decent center convergence with dynamic unplugged. Once I plug in dynamic it throws it off a bit but ill cross that bridge when I need to. But the picture looks a lot better with good center convergence for sure. And look at those colors!

[Electronic M]

Nice work!

Your making me think about restarting the resto on mine that the move out of the old apartment interrupted.

[Bill R]

It looks like you have made some good progress. However, you are still off on some of the basics. Do you have the Sam's for it? Sometimes the procedures are easier to follow in the Sam's. First things first, and remember all of them interact with each other. I notice from your last picture that you still do not have the vertical size and height quite right. Those blocks should all be the same size. The key is get the Black and white picture right, then worry about the color picture. I would turn the color off and forget for now. Try to get the linearity right first. Do not unplug the convergence board. Then work on purity, center static convergence, purity, static convergence, purity, static convergence. Repeat as needed until the one dot in the center is perfect. Then you can worry about dynamic convergence. Follow the steps in order and do not skip any. You will probably do it several times. Then recheck purity, and static convergence and tweek as needed and start over. It sounds intimidating, but by the time you run through it a couple of times you will get good at it and the entire thing can be done in less than an hour. Be sure the High voltage is correct, and the focus works properly. You may find it easier if you turn the brightness or contrast down some. You will get sharper lines. If you encounter any problems, make the necessary repair before proceeding. Now, it is time to do the gray scale adjustments. After all this you should have a nearly perfect black and white picture. Now you can turn the color up and start working on the color circuits. If you put any capacitor or part in that was not there originally, remove it. It wasn't necessary when new and shouldn't be necessary now. Be sure and check all the circuit grounds, and tube sockets. They are trouble areas. I would try a color alignment. Follow the steps in order. It is not hard. Usually you will ground a test point to let the oscillator free run and adjust the coil until the bars are stable, or only move very slowly. You will then remove the jumper and if the color oscillator, and bandpass amp are working the color should lock in solid. If not you will need to do some troubleshooting and do it again. Once color locks in it may be wrong so that will be adjusted next. You will center the tint control and adjust the transformers in the demodulator circuit for correct flesh tones and proper tint range. It is a balancing act. Now you should have a good color picture with proper tint range. Notice that unless you are using a vectorscope I have not mentioned any color bars. The early procedures use a keyed rainbow pattern, not the NTSC pattern you are using. You do still have an IF alignment issue since the color does not quite fit the black and white picture. On your color bars you can see it as the intensity of the color bar dropping off near the edge of the bar, or bleeding onto the next bar. Do carefully check the caps and resistors in the IF strip since some could have drifted off value. Replacing the drifted components may fix the problem without doing an alignment. DO NOT attempt this alignment without the proper equipment. You would need a Sweep marker generator, Oscilloscope with demodulator probe, and a bias power supply.
You are making great progress, just remember to try not to get ahead of yourself. You will end up chasing problems that may not really be there.