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  #61  
Old 02-23-2013, 07:36 PM
StratLou StratLou is offline
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Quote:
Originally Posted by Zenith26kc20 View Post
It looks like a tripler retrofit was installed. If so, be happy. As mentioned earlier, the focus dividers (little white or yellow rectangles) mounted near the tripler would split open and hiss and then arc.
Can you hear a distinct "crackle" of the high voltage coming up when you turn the set on?
As I try to find a few minutes here and there to do some testing on the set, today I managed to turn it on and listen out back for this distinct "crackle" of HV. What I did hear, and hadn't noticed before, was a consistent buzzing coming from the HV area, as best as I could ascertain by listening. The buzzing came up quickly after turning on the set. It can be heard from the back but not from the front. Should I try to pinpoint the source more closely and how can I do that with some tool (insulated auto stethescope/probe would be nice, right?!). I'm afraid if I put my ear too far in it may come back out slightly toasted. Is anyone familiar with this sound and whether it is normal or tells us anything about the issue. Thanks.
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  #62  
Old 02-26-2013, 02:24 PM
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Originally Posted by StratLou View Post
As I try to find a few minutes here and there to do some testing on the set, today I managed to turn it on and listen out back for this distinct "crackle" of HV. What I did hear, and hadn't noticed before, was a consistent buzzing coming from the HV area, as best as I could ascertain by listening. The buzzing came up quickly after turning on the set. It can be heard from the back but not from the front. Should I try to pinpoint the source more closely and how can I do that with some tool (insulated auto stethescope/probe would be nice, right?!). I'm afraid if I put my ear too far in it may come back out slightly toasted. Is anyone familiar with this sound and whether it is normal or tells us anything about the issue. Thanks.
Just putting this out there again if anyone has any ideas or can tell me what this could be. Thanks.
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  #63  
Old 02-26-2013, 05:21 PM
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That buzzing sound could be coming from the windings on the deflection yoke that are responsible for vertical deflection.
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  #64  
Old 04-26-2016, 08:59 AM
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Sorry to dig up such an old thread, but I'm supposed to be getting a set just like this soon, and in my research, I found this thread. Just wanted to know if this set was ever repaired and what the problem was.
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  #65  
Old 11-05-2019, 11:31 PM
StratLou StratLou is offline
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Hey guys,

Resurrecting my old thread for some sad news. I was never able to get around to repairing the old Zenith and life has gotten very complicated. We moved my mom in with us and are selling her house. Have no where to put the set and I don't want to just kick it to the curb so wanted to let the forum know that we would like to give it to someone who would want to restore it and possibly give it a new life. It's been really hard as we did want to try to fix it but the time was just never there. So if anyone is interested please pm me as soon as possible. Unfortunately, I think it would have to be pickup only as I think the cost and difficulty to try to ship this piece of furniture would be astronomical. I think I would need to post this in the classified section of the forum (as soon as I can figure out how and where) so that more members can see it. So anyone reading this let me know. And thanks for all those who helped in this thread over the years.
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  #66  
Old 11-09-2019, 10:55 AM
StratLou StratLou is offline
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Here's a link to the classified listing of it if anyone's interested:

http://www.videokarma.org/showthread.php?t=272222
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  #67  
Old 11-09-2019, 09:09 PM
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Lou, you may want to post on the ETF classified or in ARF. There are no doubt many New Englanders in road range of your location.
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  #68  
Old 11-10-2019, 09:26 PM
StratLou StratLou is offline
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Originally Posted by DavGoodlin View Post
Lou, you may want to post on the ETF classified or in ARF. There are no doubt many New Englanders in road range of your location.

Sorry, not sure what or where either of these are if you could explain. Thanks.
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  #69  
Old 11-20-2019, 09:39 AM
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Well, my son somehow managed to convince my wife to allow us to keep the set and take it with us when we move! So, with that in mind, is anyone still around from this old thread (or anyone new since) who can respond as to whether they would be available to help me in repairing this set as planned oh so many years ago? Thanks if anyone can respond please!
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  #70  
Old 11-21-2019, 10:54 AM
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AlanInSitges AlanInSitges is offline
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Re-reading through this old thread, that is from before my time, there was a lot of jargon in there that would probably be overwhelming to you.

Assuming you're picking up where you left off, the first thing to do is confirm that there's no high voltage: if you don't hear that static crackle when the set first turns on, then there is probably no high voltage.

Next you should double-check to make sure the circuit breaker isn't tripped. Push it in and power on the set again.

After that, the assumptions made here lo those many years ago are probably correct. There are several suggestions pretty much all of which boil down to two things:

1. Failed tripler, horizontal output transistor, or possibly flyback transformer. The tripler was replaced in the past but it could have failed again - they are a high-failure item, relatively speaking. The usual failure scenario in these sets was: Tripler shorts, which then causes the horizontal output transistor to short, which, if the circuit breaker doesn't trip to save things, will cause the flyback transformer to fail.

2. A lack of horizontal drive, meaning the signal that drives the horizontal/high voltage section isn't present.

By far the most common cause is the first one. The steps to track them down are all in the thread, but if you don't know what you're looking for it would be tough. Try this:

1. Un solder the wire from the tripler that goes to the flyback. Position it so the end is well clear of anything, and turn on the set. Hold the tip of a screwdriver about 1" from the end of the wire you just unhooked (don't touch shaft of the screwdriver, just the handle) and see if you get a little arc. Move it closer until you do. In most cases you should see a little spark there, indicating that the flyback, horizontal output transistor, and horizontal drive are all working OK and that tripler needs to be replaced.

2. If you don't get a spark or arc, and the circuit breaker isn't tripping after you reset it, it's possibly a bad horizontal output transistor but more likely the flyback is open, or you have a horizontal drive problem.

Check those things out and we'll help you from there. That's still the best TV ever made.
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  #71  
Old 11-22-2019, 12:40 AM
StratLou StratLou is offline
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Thanks for your comments in this resurrected thread. I remember, although I couldn't easily find it on a quick look back, earlier in this thread that someone mentioned that if I reset the circuit breaker to see if it was tripped and then turned on the tv, that it might damage the circuitry even further (like you mention about maybe damaging the flyback transformer)? With that in mind, would I just approach the testing you mention by just following your instructions and nothing untoward should happen? Thanks again.
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  #72  
Old 11-22-2019, 06:47 AM
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AlanInSitges AlanInSitges is offline
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Well never say never but generally speaking if the circuit breaker tripped before due to a shorted transistor or tripler, it will trip again right away. Just don't go resetting it over and over. Once is enough to tell if it's going to keep tripping.
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  #73  
Old 11-26-2019, 08:57 PM
StratLou StratLou is offline
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Does anyone have any leads as to who/where I might find any of these possible parts to repair the set, once I figure out which part(s) is/are the problem? Thanks.
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  #74  
Old 11-28-2019, 07:30 AM
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AlanInSitges AlanInSitges is offline
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They are commonly available here, on ebay, or your local electronics distributor. There's nothing unobtainable in that set. The flyback is the most unlikely but I recall others saying they have spares and parts sets in this thread.
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  #75  
Old 01-08-2020, 07:35 PM
Tim Tress Tim Tress is offline
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The first thing to do is to check the horizontal output transistor for a short. Do you have a test meter?
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