Quote:
Originally Posted by Electronic M
Ask and ye shall eventually sort of receive...Video is still wacky which makes getting a bright plain raster tricky, and getting a pattern to attempt static convergence a downright pain in the but. It would seem the initial recap left several of those lousy chalk peaking coils, and sloppily j-hooked in many of the new caps...I'm glad it is pre-recapped, but some of the workmanship, to put it kindly, is not how I would have done it. Soon I hope to bench it and go over the video circuits. Purity and convergence pics shown below represent my first attempt on a 15GP22 based set. It is a completely different process from every CRT type that followed. Most of the time I felt like I had been dropped in Brittan and asked to drive one of their backward cars on one of their backward roads. Static convergence was off by a mile when I did the purity so if it is anything like a later set then that will affect the purity, and I'm probably going to have to go back and forth between static convergence and purity a few times before it is right (only did purity once followed by one round of convergence). Static convergence is REALLY weird on this set there is the side knob (which gave me a choice of how wrong I wanted it at first) then the static magnets are similar but different from later CRTs...Specifically, there is only blue lateral action from the magnet and the DC convergence knob on the HV cage needs to be used in conjunction (and it affects all three guns)...In summary purity and convergence are sort of decent, but not perfect.
    
I'll probably be able to improve it more in the future.
For now, I plan to focus on the video circuits...The lumina channel will pass very weak video with the chroma off, but not nearly as much as it should, with chroma up it will get VERY bright but it seems like the color demod is not working correctly...Looking at the clock I should probably sleep and worry about it tomorrow. |
Tom,
That's my old CT-100, well, kind of. The CRT in it is a different one but the chassis and cabinet are the same.
The chassis was sold to me as having been restored and my reaction to the work on the chassis was the same as yours. It was making inadequate HV when I bought it, and was frankly, a complete trainwreck. If I had known how poor the previous "restoration" was, I'd have run screaming in the opposite direction. In addition, every single IF transformer and adjustable coil in that set had been screwed with. I focused on alignment and let the caps go for the time being. I got it to the point where I could get some semblance of a signal through the IF strip and finally got frustrated, shoved the chassis back in the cabinet, and eventually sold it to John. I never did any of the recapping. Given my experience with recapping from this individual in my 630TCS, every single capacitor will need to be checked to ensure it was installed correctly. IIRC, there were also some originals tucked up in there somewhere...
I'm not sure if John did any work with it or not. I'm inclined to believe the chassis is exactly as it was left when I had it. I was able to get good strong audio and decent looking luma through it around the time I gave up on it; I watched an entire episode of the Honeymooners on it and it OK looking. Marginal, but watchable. It will need another check of the alignment. I can guarantee it is still fairly far from usable. As far as I know, the chroma sections on that set never worked post-"restoration".
Best of luck, as you'll need it.
-Ben