[ohohyodafarted]

I agree with what Wayne had to say. To this I will add that there are two versions of the wiring for the convergence circuit. One of them works a bit better than the other, I don't remember which one is the better one. I would presume it is the version used on the ctc4A. I will have to find out when I get my ctc4 up and running in about 4 to 6 weeks after the cabinet is finished. Chassis is 90% done but I will not waste my time converging the picture on my 21AX crt test jig.

BAck in the early 70's is the last time I had the chance to converge a 4 that I owned when I was in my 20's. But I do recall that I was never happy with the convergence. No matter how hard I worked at it, it was always off somewhere. I learned to just accept it. I can tell you that it will never be as good as the convergence that I got on my ctc5 Wingate.

But Wayne is correct. Use a cross hatch with the static convergence out about 1/8" in the center. Then do your best to create lines that are as close to parallel and equidistant as you can get them using the dynamic controls. Then pull the 3 images together using the static magnets on the convergence yoke. Pull red and green together first, then drop the blue vertically and finally use the blue lateral to move it left and right. It will always be a comprimise and will never be perfect. I try to get a good average across the entire screen. I do not strive for perfection in the center, because that will only cause the edges to be GROSSLY out of convergence. A little bit off in the center usually allows for much more acceptable convergence in the outer areas. I never use dots, I always use cross hatches because you can see the direction of the displacement better as you are in the process of making the adjustments.

AS I recall the phasing coils will have a sweet spot where it will cause maximum deflection of the amplitude controls. Once you find the sweet spot, you won't have to adjust the phasing coils very far in either direction from the sweet spot. I also recall on my old 4 some of the controlls had little to no effect.

That is about all I can offer. Less than perfect convergence is just something a person learns to live with. And I don't know why convergence on a 4 should be problematic. After all, the convergence on my 21ct55 is dead nuts on, after it's warmed up. You would think that it would be as good or better on a 4, being that it's a generation later.

Good luck..