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  #46  
Old 04-22-2018, 08:43 AM
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zeno zeno is offline
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Fear not the 13" !! I would rather do them all day than anything else.
SO easy & its on the bench instead of getting up & down. As far as the
B&W console goes a better set was NEVER built. They are almost immortal.
The only weak spot on them was the audio could be buzzy & hard to tame.
That was common to most Zenith tube sets.

73 Zeno
LFOD !
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  #47  
Old 04-23-2018, 03:15 PM
albanks albanks is offline
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Quote:
Originally Posted by Electronic M View Post
Display crosshatch on screen loosen yoke bracket rotate yoke while looking at screen for straightness tighten bracket when straight.... easy peasy lemon squeezy.

10-13" tube Zeniths are VERY SERVICEABLE you just need to figure out how to get them apart and get used to the difference in layout...compare one to a cheap GE or 5 and you'll appreciate the Zenith.
OK cool thanks a lot.
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  #48  
Old 04-23-2018, 03:16 PM
albanks albanks is offline
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Quote:
Originally Posted by zeno View Post
Fear not the 13" !! I would rather do them all day than anything else.
SO easy & its on the bench instead of getting up & down. As far as the
B&W console goes a better set was NEVER built. They are almost immortal.
The only weak spot on them was the audio could be buzzy & hard to tame.
That was common to most Zenith tube sets.

73 Zeno
LFOD !
There was literally no room to even get tools toward the bottom of the electrolytic to clip the wires but if you guys say it is possible to work on them I will take another look.
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  #49  
Old 04-23-2018, 04:08 PM
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Quote:
Originally Posted by albanks View Post
There was literally no room to even get tools toward the bottom of the electrolytic to clip the wires but if you guys say it is possible to work on them I will take another look.
I've never seen it hard to do in a Zenith TV. I've seen a lot of Zeniths, but I've not seen everything. Usually, they make it easy in portables assuming you've sufficiently separated cabinet and chassis. Worst cases I've seen in other American sets is you have to remove a thing or two on the chassis to get at a can. If it is stumping you then, by all means, post some pics of the area, and one of us will probably remember a trick or figure it out from looking...We are here to help.
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  #50  
Old 04-23-2018, 08:34 PM
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zeno zeno is offline
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Assuming its a 13GC10 or later HC, JC, KC, LC..........
Remove two 1/4" screws in top corners of chassis. There may also
be also one or two along the sides. Now the chassis will tilt down.
The can is behind on the sub-chassis. MOST were mounted on
a small steel plate held by a 1/4" to the steel sub-chassis. Remove the
bolt & it flips out and its easy to change. If you need more room pull the
four 1/4" under the set & the chassis will come out. Take your time
so you dont damage the CRT board or pull any wires. At that point
everything unplugs if needed. Zenith always put serviceability on top.
The only mistakes I remember were the dial lamps & cans in the
hybrid sets. They actually took a few minutes to change !

73 Zeno
LFOD !
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  #51  
Old 04-24-2018, 06:59 PM
albanks albanks is offline
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Pictures of my two 13" Zenith's coming soon. One of them is purple and appears to have been made overseas. I am guessing this is indicative of the set being made after Zenith's glory days. I would say both sets are mid to late 70's.

Before I get to the 13" sets, as I have been continuing my education here and around the 'net I have begun to second guess my work on the 19".

Questions 1 & 2

1) Since rebuilding the cans turned out to be too laborious and annoying (and I don't give a damn what it looks like inside) I simply clipped the wires and soldered the new electrolytics in below. Now here is the thing. For the negative grounding - I simply soldered that lead to wherever was an available metal space on the chassis. Given that this is a (I think) a hot chassis design - is that OK? As far as shorting out or any other dangers? I think I have heard members here refer to my set as transformer less/ hot chassis and I have been reading some horror stories so I thought I'd better ask.

2) The insulation on the filter choke is iffy. It is cracking and splitting apart. Can I just join it back up with electrical tape or leave it alone?

OK, thanks again for helping a real NOVICE
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  #52  
Old 04-24-2018, 07:45 PM
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1.) Were these bare metal cans with the outer metal shell attached directly to the chassis? If yes then all chassis ground points should be valid negative terminals for the new caps. If no then I assume the originals had a cardboard sleeve and the 3-4 negative mounting ears did not connect to chassis but instead connected to an insulating wafer that is riveted to the chassis in two places...Those have a separate negative lead (or several if used as a terminal strip for the neg bus) going to their outside terminal(s)...You MUST connect the new caps' negative leads to the SAME negative bus wire as their can is on.

Some sets only chassis grounded their caps, some only used the floating negative bus, some did both, some had the negatives on different caps on different busses...It depended on how complex the power supply was. Make sure the replacements negatives are on the same negative as the originals.

2.) sometimes the outer paper/cellophane/plastic layer peels. If the winding has not shorted or shorted to the core all should be fine...Albeit less pretty. Look it over maybe ohm it out...If it is fishy you should notice.

Stress a bit, but not too much. We all goof up something, often in the power supply, at least once...Having a variac helps reduce damage risk on first power up.
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  #53  
Old 04-24-2018, 08:21 PM
albanks albanks is offline
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Quote:
Originally Posted by Electronic M View Post
1.) Were these bare metal cans with the outer metal shell attached directly to the chassis? If yes then all chassis ground points should be valid negative terminals for the new caps. If no then I assume the originals had a cardboard sleeve and the 3-4 negative mounting ears did not connect to chassis but instead connected to an insulating wafer that is riveted to the chassis in two places...Those have a separate negative lead (or several if used as a terminal strip for the neg bus) going to their outside terminal(s)...You MUST connect the new caps' negative leads to the SAME negative bus wire as their can is on.

Some sets only chassis grounded their caps, some only used the floating negative bus, some did both, some had the negatives on different caps on different busses...It depended on how complex the power supply was. Make sure the replacements negatives are on the same negative as the originals.

2.) sometimes the outer paper/cellophane/plastic layer peels. If the winding has not shorted or shorted to the core all should be fine...Albeit less pretty. Look it over maybe ohm it out...If it is fishy you should notice.

Stress a bit, but not too much. We all goof up something, often in the power supply, at least once...Having a variac helps reduce damage risk on first power up.
Thank you for your reply and valuable knowledge. Please see attached pictures. I green check marked the type of capacitors my set has. I am guessing by the information you provided I am in the clear. That is very reassuring.
Attached Images
File Type: png Capture.PNG (75.5 KB, 30 views)
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  #54  
Old 04-24-2018, 08:49 PM
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Electronic M Electronic M is offline
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Those are the two types I was describing. It sure looks like your in the clear. Good luck.

I've been known on sets where the can area is cramped and the negative is chassis (or the negative line is convenient) to move the new lytic elsewhere on the positive line to a place with more room like what you describe...What you are doing is a valid and logical layout change.
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Zenith: The quality stays in EVEN after the name falls off!
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  #55  
Old 04-25-2018, 07:43 AM
albanks albanks is offline
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Quote:
Originally Posted by Electronic M View Post
Those are the two types I was describing. It sure looks like your in the clear. Good luck.

I've been known on sets where the can area is cramped and the negative is chassis (or the negative line is convenient) to move the new lytic elsewhere on the positive line to a place with more room like what you describe...What you are doing is a valid and logical layout change.
Thanks man, that's great to hear. I think I will fire the set back up then.
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  #56  
Old 05-07-2018, 08:08 PM
albanks albanks is offline
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I just want to bring this thread back up for a second. Someone earlier mentioned arcing and the gunk on the crt near the hv connector. I did skip this step but I think it would be good to clean due to some obvious symptoms. I do remember I had a tough time cleaning it. Any tips as far as cleaners or techniques or do I just use a dry cloth and muscle it off? It may sound silly but I couldn't clean it well last time the back of the set was off.
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  #57  
Old 05-07-2018, 11:22 PM
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Electronic M Electronic M is offline
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Rubbing alcohol is my favorite for the area around the NV connection on the crt, follow up with glass cleaner for a good shine. Remember there is a black aquadag coating as close as 2" to the HV connection. The dag needs to be there the dirt not so much...Telling them apart takes experience.
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Zenith: The quality stays in EVEN after the name falls off!
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  #58  
Old 05-08-2018, 09:51 PM
albanks albanks is offline
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Originally Posted by Electronic M View Post
Rubbing alcohol is my favorite for the area around the NV connection on the crt, follow up with glass cleaner for a good shine. Remember there is a black aquadag coating as close as 2" to the HV connection. The dag needs to be there the dirt not so much...Telling them apart takes experience.
rubbing alcohol works for me. There is about a 1"by2" area missing DAG, I put a piece of electrical tape over it. DAG seems expensive. Do I need to buy some just to coat this small area? The reason I am cleaning the gunk near the HV is the occasional pops and hisses which I guess is the arkover.
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  #59  
Old 05-08-2018, 10:44 PM
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Originally Posted by albanks View Post
rubbing alcohol works for me. There is about a 1"by2" area missing DAG, I put a piece of electrical tape over it. DAG seems expensive. Do I need to buy some just to coat this small area? The reason I am cleaning the gunk near the HV is the occasional pops and hisses which I guess is the arkover.
A picture would help... blind advice is don't put any day closer than 1.5" to the HV connection, and any piece smaller than a dollar missing is okay as long as there are no islands. All dag must connect to all other dag any unconnected islands must be connected with a conductor (ideally another layer of dag) or removed... islands arc to each other and that is very bad.

Slip Plate was under 15$ on wallmarts website last I checked...it makes a great dag substitute.
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Zenith: The quality stays in EVEN after the name falls off!
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  #60  
Old 05-09-2018, 01:33 PM
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Notimetolooz Notimetolooz is offline
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Quote:
Originally Posted by albanks View Post
rubbing alcohol works for me. There is about a 1"by2" area missing DAG, I put a piece of electrical tape over it. DAG seems expensive. Do I need to buy some just to coat this small area? The reason I am cleaning the gunk near the HV is the occasional pops and hisses which I guess is the arkover.
The tape wouldn't help anything and of course if you remove it you will probably pull up more dag. The snapping could be coming from other places besides the CRT. Turn the lights out and look around the flyback and HV rectifier.
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