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  #1  
Old 10-28-2016, 12:50 PM
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Exclamation HELP with Zenith 25DC56!

Got TWO Zeniths this morning for $15 a pop. The color one works, but the tube is tired. Going back this evening or tomorrow to fetch them.
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Last edited by TUD1; 11-06-2016 at 05:31 PM.
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Old 10-28-2016, 02:22 PM
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Now you have TV twins, sweet! You're getting into the same collecting league as Doug. Made me think of his Quasar trio.

Ha, gotta love that sign in the foreground. Looks like that stack was an accident waiting to happen before you got there.
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Old 10-28-2016, 03:38 PM
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Nice! The top set looks like a 14N22 series monochrome...It and the RCA 630 are about tied for longest lived monochrome chassis...The Zenith is in a league of it's own if you count years of production essentially unmodified from the original design.

I dig that chair in the background, I'd buy it with the sets in your shoes if the price is sane.
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Zenith: The quality stays in EVEN after the name falls off!
What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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Old 10-28-2016, 04:43 PM
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Quote:
Originally Posted by Jon A. View Post
Now you have TV twins, sweet! You're getting into the same collecting league as Doug. Made me think of his Quasar trio.

Ha, gotta love that sign in the foreground. Looks like that stack was an accident waiting to happen before you got there.
That is so awesome to be compared to Doug - the King of Zenith. When I got there, I only saw the color set, but when I went to pay, the ladies told me that there was yet another old console TV. It was in the back room marked "NOT INCLUDED IN SALE." I manhandled it and put it on top of the color set, and one of the ladies put sold stickers on both. We took the old beat up F150 for a spin to go pick them up. I plan on watching The Big Bang Theory tonight on the 25DC56 - it has high voltage and the 22-5001's have been replaced. What could possibly go wrong?
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Old 10-28-2016, 06:13 PM
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Quote:
Originally Posted by TUD1 View Post
I plan on watching The Big Bang Theory tonight on the 25DC56 - it has high voltage and the 22-5001's have been replaced. What could possibly go wrong?
Famous last words...

According to Murphy's law the motor run cap for the VRT, the lytic under the chroma module, one or more of the 3 video out transistors, the module contacts and or the tuner contacts will ruin your program now that you've said that.
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Zenith: The quality stays in EVEN after the name falls off!
What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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Old 10-28-2016, 06:18 PM
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Take this, Electronic M!
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Old 10-28-2016, 06:19 PM
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Moar.
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Old 10-28-2016, 10:31 PM
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Quote:
Originally Posted by Electronic M View Post
Famous last words...

According to Murphy's law the motor run cap for the VRT, the lytic under the chroma module, one or more of the 3 video out transistors, the module contacts and or the tuner contacts will ruin your program now that you've said that.
Let's not forget the socketed transistors on the 9-57 module. I've had intermittent contacts that caused reduced horizontal sweep, partial and complete loss of horizontal sync, pincushioning and no HV. One module I subbed in had a bad transistor; no HV until I changed the transistor.

That being said, did it last through the show?
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Old 10-29-2016, 08:38 AM
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It sort of made it. The only problem I'm having (besides convergence and purity) is that there is an intermittent connection in the tuner. Every once in a while, it will get a clear picture, but after a while, it just fuzzes out with snow and crap.
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Old 10-29-2016, 10:23 AM
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Quote:
Originally Posted by TUD1 View Post
It sort of made it. The only problem I'm having (besides convergence and purity) is that there is an intermittent connection in the tuner. Every once in a while, it will get a clear picture, but after a while, it just fuzzes out with snow and crap.
Yup...These days whenever I open a set I've not opened before to work on it I try to clean the tuner while I'm in there....Especially if the tuner is a pain to get at.

These CCII are pretty darn reliable aside from dirty tuners and contacts, and if the safety caps are good they should last. The other issues I've personally dealt with or seen once or twice, but are not very common.
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Zenith: The quality stays in EVEN after the name falls off!
What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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  #11  
Old 10-29-2016, 12:37 PM
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That happened with mine as well. The small opening in the back of the VHF tuner, on the top left, is a convenient place to spray contact cleaner where it will flow to where it's needed. Better that than pulling it and opening it I figured. You mentioned Radio Shack contact cleaner which is what I use. Well, it's no longer Radio Shack here, it's now The Source. Anyway, giving it a good spray and cycling the tuner a few times worked like a charm.

I see vertical linearity needs a touch-up as well.
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  #12  
Old 10-29-2016, 01:45 PM
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I'm kind of starting to prefer this set over my other 25DC56 that I got it April. I like the warm tones it has better than the darker one. Just for comparison, here is the other set.
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Last edited by TUD1; 09-22-2017 at 01:23 AM.
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Old 10-29-2016, 07:07 PM
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I think this TV is trying my pi$$ me off. Remember the problem I was having with the fuzziness? I found the source of the problem. It's the connection from IF wire at the tuner, where it plugs in like a composite RCA cable. I cleaned the connection countless times, and it will get a crystal clear picture, then if you look at it too hard, the fuzzing connection messes up again. I think it is the tuner, not the cable itself. The cable is soldered together. I tried bending the prongs around the tuner connector, but nothing worked.
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Old 11-06-2016, 05:17 PM
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I tried cleaning every connection I could find on the tuner to the chassis to try to get rid of the awful fuzziness. It's incredibly frustrating when you clean and clean and you turn the set on and have an excellent picture, and then after 15 seconds it goes fuzzy and awful again. I cleaned the inside of the tuner with spray and a rag, cleaned both IF wire connections, I'm at a loss.
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Last edited by TUD1; 11-06-2016 at 05:33 PM.
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  #15  
Old 11-07-2016, 01:35 PM
Alastair E Alastair E is offline
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Intermittent RF amp transistor in the tuner...

Used to be a popular issue here in the day.
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