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-   -   RCA Victor 21-T-8205 issues (http://www.videokarma.org/showthread.php?t=268959)

Electronic M 05-31-2017 01:33 PM

BTW if the wave appears as a horizontal bar that slowly rolls vertically, then it is likely the Power supply lytics.

Zenith26kc20 05-31-2017 01:53 PM

Usually power supply electrolytics start off waving then as they warm up thermally they work. If the power supply electrolytics are failing after they have been on a while they start to run warm to the touch. Be careful, my RCA CTC-9 almost had it's power transformer burned up by a leaky electrolytic.
I would try subbing a horizontal oscillator tube as heater to cathode leakage can also produce the symptoms you are describing.
What signal sources are you using?

ThePlague 05-31-2017 06:30 PM

Quote:

Originally Posted by Zenith26kc20 (Post 3184736)
Usually power supply electrolytics start off waving then as they warm up thermally they work. If the power supply electrolytics are failing after they have been on a while they start to run warm to the touch. Be careful, my RCA CTC-9 almost had it's power transformer burned up by a leaky electrolytic.
I would try subbing a horizontal oscillator tube as heater to cathode leakage can also produce the symptoms you are describing.
What signal sources are you using?

I'm using a kindle fire into a hdmi to av converter that then runs into a rf demodulator. This combination is able to stave off the issue the longest. As for the waves.. imagine a side ways V that goes through and distorts the image. It does not roll. A combination of the tuner fine tuning, contrast control, and a little horizontal lock and can usually bring it back for another hour and then not much seems to help it.

ThePlague 05-31-2017 06:35 PM

Here are a few examples of some of the issues that will happen.

http://i1136.photobucket.com/albums/...image1%205.jpg

http://i1136.photobucket.com/albums/...image2%201.jpg
Notice that grey ish line in the middle. Under normal conditions that line is straight and centered.

irext 05-31-2017 07:32 PM

I would recap it and measure resistors whilst performing the recap. You've already found crook caps in the vertical and hor circuits so it's highly likely that there are others just as bad elsewhere in the set. Once that's done you can address any remaining faults.

Bill Cahill 06-01-2017 12:41 AM

That is correct. Some of those mica caps also look suspect. Looks like one paper cap had exploded from being shorted.
I agree with them that say replace all paper caps, and, electrolytics so you will have a trust-worthy set.
I also see why the vertical has fold over, more bad caps. The audio caps are always bad. And, I've actually found damaged controls from shorted caps.
Bill Cahill


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