Digging into the CTC-9

[leadlike]

I picked up a '9 Winslow on Craigslist a few months back:

http://www.videokarma.org/showthread.php?t=246304

As found, it had a pretty bad cataract, and produced a sickly green picture that barely held vertical or horizontal sync. After about two minutes of running, I could see a little bit of smoke coming from the HV cage.

I elected to do a full recap. While 90% of the caps in this set are of the modern type (mostly maroon, but some orange drops as well), about a quarter of them tested leaky on my cap checker. I noticed on those that did not test leaky, that when I went to check their values, that the cap checker eye did not open nearly as much as it normally would for a new cap of the same value. For fun, I took some low ohm resistors (5 and 10 ohms) and put them in series with a new cap and tested it-it tested a lot like the older caps. So while this isn't definitive proof, it certainly looks like the older caps had some high ESR.

No issues with the recap. The set powered up, with no smoking. I next decided to tackle the cataract. The picture tube was a 21fj that tested brand new. Playing the tv now, I could see that it produced an excellent picture. I took it to a friend's shop, and we spent all day Saturday working on the thing. First we tried the hot wire method. Heat would not do anything to this stuff. Even stabbing my soldering gun into some of the gunk we had scraped off of the side did very little to it. This was after preheating the tube, etc. Whatever this PVA was, it wasn't going to come off that way.

The safety glass came off perfectly, as outlined on that great series of Youtube posts. Heat guns and work lights saved the day. Well, for a while. After the tube had cooled, I was wiping down the picture tube face with a paper towel before applying the double sided tape when it imploded. That is to say, I had both hands in contact with the face of tube when it seemingly vanished.

When I opened my eyes (I was wearing safety glasses, luckily) my poor friend was hunched over the hood of a car, obviously in pain. I knew I had to have been hurt, but I ran over to him and we began to assess just how badly we were injured. He had taken a large piece of glass straight into the face-it put a nice slice into his chin and under his nose. My worst cut was a piece had sailed past my head, making a neat slice across the middle of my ear, nearly going all of the way through. Needless to say, things could have been much worse. I got cut in about ten places, and holding the bulky shirt I was wearing up to the light, it looks like it has been blasted by rock salt. The sound was tremendous-even though the garage door was down, it was loud enough to bring the neighbors on all four sides of the house over to investigate. I'd wager it was on the sound level of a quarter stick of dynamite going off-it certainly had my ears ringing for the rest of the day.

So that was a bit of a scary setback-there is a LOT more to that cataract removal story-we tried every possible method to pull that thing off without going to the heatgun method, but that would be just too much to write here. After all, there is a tv that needs attention here....