I've got an RCA AT113 chassis on the bench right now, that came in with a very bright picture, retrace lines, and poor focus. If I turn the screen control all the way down, and turn the focus control all the way clockwise, it actually has a pretty decent picture, though obviously something is wrong. Before I start troubleshooting, I just wondered if this is a known problem in this chassis, and if so, what component(s) are to blame. Thank you for your help.
RCA ATC-113 Model F27650
I wanted to add that the picture blooms very badly when the screen control is opened up even slightly. The CRT appears to be fine when the screen control is set turned completely down. It doesn't appear to be a shorted CRT, although anything is possible. I am completely unfamiliar with this chassis. I have been a tech for over 40 years, but have been retired for the past 5 because of health problems, and not up to date anymore. On a sidenote, I just wanted to mention, that it's very hard to get out of a business, you have devoted your life to, so that's why I am now doing it just part time, as health allows. I started with black and white TVs. My father who ran a shop since the 30s, brought the first color TVS to our home town of Ottumwa Iowa. Even though technology has advanced greatly over the years, I still miss the early years, when it was all so exciting, and new. I remember people thought I was a wizard when I made their TV come back to life. It's just not the same anymore.
I am not familiar with the chassis, because I have been out of the business for about 4 years. What are the two independent results from adjusting the 2 controls on the flyback? What are the voltages and waveforms like on the CRT neck board when the picture is bad, and when it is good? Do you have a probe that can measure the focus and G2? A bad flyback (divider) wouldn't surprise me, but it'd be nice to have one to swap in to verify that long shot.
Tom
On Thu, 18 May 2006 09:49:26 -0500, BigMike put finger to keyboard and composed:
I'm not familiar with your set, but high voltage regulation problems are often caused by tripler faults. In your case the tripler is probably internal to the FBT so there's not much you can do. Check the B+ first, though.
- Franc Zabkar
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