Before Convergence Adjustments
 

I am in the process of performing the static and dynamic convergence adjustments on a 1960 RCA roundie. It has a ct-11 chassis. I recently purchased a book titled RCA Color TV Troubleshooting pic-o-guide. It is very helpful in guiding you through the static and dynamic adjustment process. In the book it says to check Size, Linearity and Centering before any of the convergence adjustments are touched. My question is this ; is there a standard or preferred method of performing the size, linearity and centering adjustments? I have a BK color pattern generator that I use to produce an 11x7 crosshatch pattern for the dynamic convergence adjustments. It also has a 1x1 crosshair pattern. Any input as to the size linearity and centering methods would be greatly appreciated.

1. put the chrosshairs on screen, center the picture vertically and horizontally. Check height and width so that you have a 1" overscan on the face of the CRT.

2. put the crosshatch up, make linearity adjustments. For horizontal, you have to read horizontal output tube cathode current and tweak the lin slug for minimum reading. For vertical, just mess with it till you have uniformly sized squares top to bottom.

3. make static convergence adjustments. With the crosshairs, make perfectly converged white lines in the center of the screen.

4. make dynamic convergence adjustments. FOLLOW THE MANUAL RELIGIOUSLY! Not gonna provide my own spin on how it's done anymore, because I found through trial and error that the factory got it right when they wrote the instructions.

I like the CTC-4 method myself, where you displace the lines a little to make sure they are straight, then bring them back together with the neck magnets. To each their own.

miniman82 gives good advice.
My bit of advice is this. You aren't going to have a perfectly converged set when you are through. No how, no way. SO...don't drive yourself crazy trying to do so. Concentrate on the center of the screen. Forget the far edges.
Let us know if you have any troubles. I've converged a few over the years.
Main thing is to have fun.
Phil

beside the vert height and lin, make sure the purity is correct BEFORE you touch the convergence

Don't forget to degauss the set and make sure all of the stuff is properly positioned on the CRT neck.

Yes, of course. The red purity magnet will cause the beams to move around, so don't do this unless purity is done first.

Also be prepared to degauss the set again if you move it to another place after doing the final setup & convergence.

This article describes some of my adventures in learning how to converge my first CTC-11:

http://antiqueradio.org/RCACTC-11Television.htm

If you're lucky, you will not need to do so many repairs along the way.

The Pict-O-Guide is well written and very informative, but I followed the Sams convergence instructions and (eventually!) got good results. There's no shame in repeating a procedure; it may take a while to get the hang of what various adjusters actually do. And, as already mentioned, you may need to accept some little compromises in the end.

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

Making the static and dynamic convergence adjustments on a vintage color tv can be very difficult for someone like me who tends to be a perfectionist. I guess there just has to be compromise. As someone said in an earlier post, there is no such thing as a "perfect" convergence with every corner lined up just righr. I guess with these old sets you just have to do the best that you can. I find that it helps sometimes if I just stop what I am doing and come back and try again the next day.

Having been in the sales & service end back in the day, I can vouch that even brand new, convergence around the edges was always a compromise.

This is especially helpful in early sets, where the dynamic convergence was AC coupled, meaning it affected the center and both edges, but left the half-way points alone. Later sets used diodes or some such in the convergence circuit to force the center to stand still when the dynamics were adjusted.

If you have the Pict-O-Guide for your vintage of set, following that should get you there.

Many thanks to everyone for your input on the convergence issue. I have what I think is an acceptable compromise with all of the static and dynamic convergence adjustments. It took alot of adjusting and readjusting but I think I have found a middle ground. From reading some of the posts it made me realize that it just can't be perfect. Just as someone said, even when they were brand new, they weren't perfect. I am going to put the back cover on this 52 year old tv and leave it alone. But I will always have to fight the urge to to "just tweek it a little more".

These sets often need follow ups if they see a good amount of use, and I tend to tweak on every follow up and tend to do better most times.

As parts drift in value over time, it can become necessary to readjust the convergence as required to get acceptable results. I have only ever seen one roundie that had perfect, and I mean perfect convergence. You'll never guess- it was one of those price leader 17MT80 Philco hybrids! I've never had another set before or since that was as good as that one, they have all been a compromise. It was just amazing, not a single misconverged beam even at the extreme edges of the screen. I sold it to a guy in Chicago not long ago.