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-   -   1964 Zenith 5111 comes to life! (http://www.videokarma.org/showthread.php?t=250512)

Tubejunke 03-16-2011 09:54 PM

1964 Zenith 5111 comes to life!
 
I mentioned acquiring this metal cabinet "roundie" several months ago. I was looking for a Sams PDF at the time and probably mentioned the sets condition as it was. The set was powered up slow on a 100 watt bulb for maybe an hour and a half. At full potential the horizontal outputs plate was red and there was no HV or sound other than some crackles and pops, and smoke coming from the HV cage. Naturally, I didn't keep it powered up very long in that condition.

The other night I decided to test some tubes and what I found at first attempt was a marginal horizontal oscillator, so I replaced it and the H. output still had a red plate, but not as bad. I saw an arching in the HV rectifier, so I pulled that and the regulator which were both marginal on a basic emissions test (not mutual conductance). The smoke that I mentioned seemed to be coming out of the base that the HV rectifier plugs into. I replaced both of those tubes and powered it back up. BAM! A perfect white (ish) raster that seemed to be stable. Upon another visual inspection I noticed the mixer tube glowing like a light bulb. When I pulled it I could see that it had lost vacuum, or at least some as it had a milky look, yet the filament was not burned out as I presume that it would under zero vacuum. So, I replaced that tube and powered it up again with the VCR attached and next thing I know I am watching one heck of a rich and pure color picture. Frankly, I could not believe the outcome as I have not replaced the first component beyond the tubes mentioned. I have heard about these Zeniths being super tough, but anyone who has read my posts about my trials and tribulations with my 59 24" Space Command that to this day will not play should understand, I began to wonder if Zenith was the product for me.:scratch2:

This story is great, but I don't want to make it too great. The color picture is real nice, all things considered, but there was a touch of bleeding color around images, so I know that some alignment is in order. Too bad I don't possess any of the equipment needed to properly align color TVs. When I push the service switch the horizontal line is mostly white with misalignment on both outside edges, to about 3" inward. Maybe I can touch up the color without any fancy equipment that I don't have the money for, or other than this set, any use for. The rest of my collection is 40-50s black and white. I had a few "roundie" color sets when I was a kid and they could be found pretty cheap, if not free. I just lately started seeing the nostalgia in the early color sets, so I guess I got lucky with a decent Zenith. :thmbsp:

miniman82 03-16-2011 10:06 PM

:worthless

marty59 03-16-2011 11:11 PM

Sounds like you have a convergence issue, provided you can adjust for a decient gray scale and seeing good color and flesh tones being produced afterwords. Let's see some pictures!

Tubejunke 03-17-2011 09:10 AM

OK! Pictures coming as soon as I get some camera batteries..........

Zenith26kc20 03-18-2011 09:58 AM

That's one of my favorite Zeniths! They can produce fantastic pictures!

Phil Nelson 03-18-2011 01:51 PM

Quote:

Originally Posted by Tubejunke (Post 2997844)
mostly white with misalignment on both outside edges, to about 3" inward. Maybe I can touch up the color without any fancy equipment

In Sams, the convergence board & procedure for your set looks similar to my RCA CTC-11. You don't need fancy equipment to adjust convergence. It is basically looking at the screen and turning the little adjusters. No doubt you'll have an easier time than I did with that CTC-11:

http://antiqueradio.org/RCACTC-11Television.htm

One thing you'll need is a test pattern generator. If you try to adjust convergence while watching live TV or looking at a still picture of Howdy Doody, you'll probably make it worse. In the past I have referred people to a web page that lets you make a test pattern DVD. When I checked that site today, my browser gave me an alert, so nix on that for the moment. You can find used pattern generators pretty cheap at swap meets or on eBay.

For convergence, you use a black and white pattern. I use a crosshatch most of the time.

In terms of order, convergence is just about the last thing you address. Prior to that, you need to have good "black and white" geometry (height, linearity, etc.). You also need to degauss, adjust purity and grayscale, and so on.

Perhaps you lead a charmed life and those old electrolytics will last forever. If it were my set, I'd replace 'em and sleep better at night.

Phil Nelson
http://antiqueradio.org/index.html

Tubejunke 03-18-2011 10:11 PM

Thanks Phil for the lowdown on setting up the color set. One thing that I can say is that after the second viewing yesterday the "bleeding" was less than the first go around. I have resurrected quite a few old sets that were working when stored and after a little kicking and screaming they come to life and often do OK under my limited viewing demand. It seems to me that after all of those years "asleep", the sets get better and better with limited play sessions. Either that or they play for a few minutes and then give out. I hope this case is the former! Now if I were to try to make something vintage a daily viewer I would definitely want to re-cap the set from the get-go. Right now I simply don't have the money or the time for the recap. I graduate form an electronics degree program in May and hopefully I will be able to find, well, the way thing have changed in America, A JOB! It would be great to land something that pays well in the field straight out of the gate, but I'm not counting on that. I think that this set would be a great candidate for restoration eventually. The control door is a bit tattered and I would like to find a channel knob that is not as well worn as mine.

Anyway, I hope to have some pictures of the set soon since someone informed me that words are no good without pictures. I think I will leave my opinion of the opinion to myself. If I were asking a very technical question in a thread I would see the necessity, and just for the record; I have a dial-up connection, so it is a bit of trouble to upload pictures as compared to a high speed connection. For the money, I'll take dial-up any day over high speed for my current needs. There are libraries and colleges that have all of the high speed that I need! LOL!

Tubejunke 03-18-2011 10:27 PM

Quote:

Originally Posted by Zenith26kc20 (Post 2997952)
That's one of my favorite Zeniths! They can produce fantastic pictures!

Thanks! The first thing that I noticed is that the color seems really (looking for the right words) alive(?)! To me the Zenith's color seems as good or better than way more modern standard definition crt sets! We TV people must be as weird as people seem to think that the hobby is! :D I would just as soon look at this set as some plastic HD flat screen! Certainly I can see that HD is far more, well, defined! LOL! To me the HD picture almost looks unreal where the good tube (crt) sets produced more lifelike images.

ctc17 03-18-2011 11:01 PM

Quote:

Originally Posted by Tubejunke (Post 2997992)
Thanks Phil for the lowdown on setting up the color set. One thing that I can say is that after the second viewing yesterday the "bleeding" was less than the first go around. I have resurrected quite a few old sets that were working when stored and after a little kicking and screaming they come to life and often do OK under my limited viewing demand. It seems to me that after all of those years "asleep", the sets get better and better with limited play sessions. Either that or they play for a few minutes and then give out. I hope this case is the former!

I see this on just about every used set I wake back up. I call it secondary infant mortality/break in.
I have a feeling its due mostly to things drying out. Moisture in caps, coils and transformers...resistors..everything, as well as the tubes 'burning the dust off'.
Also the parts that are going to fail in the next 2 years will fail in the first few days. Thats the infant mortality part.

compucat 03-19-2011 08:36 PM

Quote:

Originally Posted by Tubejunke (Post 2997993)
Thanks! The first thing that I noticed is that the color seems really (looking for the right words) alive(?)! To me the Zenith's color seems as good or better than way more modern standard definition crt sets! We TV people must be as weird as people seem to think that the hobby is! :D I would just as soon look at this set as some plastic HD flat screen! Certainly I can see that HD is far more, well, defined! LOL! To me the HD picture almost looks unreal where the good tube (crt) sets produced more lifelike images.

I have a 1965 Zenith roundie and I agree that the color is very vibrant. Reds in particular are deep and rich. The flesh tones are warmer than on many modern sets. Although everyone thnks I am weird for this but I actually prefer the round screen shape. I don't really like the 90 degree angles and hard edges of today's rectangular screens. Widescreen is great for movies and computers but I like my TV to be circular or very heavily curved like the 1950s sets.

marty59 03-20-2011 09:16 AM

I've been slowly progressing on my Zenith 5131/chassis 25LC30 but I've got some other projects ahead of it. I do have a soft spot for these old Zenith roundies!
It's good that yours is showing some positive potential as it will be a fun project when the time and resources are there for you.

Tubejunke 03-20-2011 02:02 PM

Quote:

Originally Posted by compucat (Post 2998072)
Although everyone thnks I am weird for this but I actually prefer the round screen shape. I don't really like the 90 degree angles and hard edges of today's rectangular screens. Widescreen is great for movies and computers but I like my TV to be circular or very heavily curved like the 1950s sets.

That is exactly the way I am, and always have been. Actually, I think what started my interest in older TVs was seeing sets like this still in living rooms as a kid in the 70s and still as a young adult in the 80s. I remember thinking that they were, in some strange way, simply more interesting to look at; on or off! That interest led me to acquire a few of them at different times throughout the 80s. I would simply wander into one of the then plentiful TV repair shops where they would often have repaired sets that people had not come back to pay the bill on. Sometimes they would give me sets gladly to make room. Seems like I paid $10 for a nice remote RCA set that performed fine for a few years. Eventually the remote control section started acting up, so I just turned it off. Heck, even in the 80s having remote control was still a non-essential creature comfort and it really didn't matter. It was cool if you had it, and still OK if you didn't. Back then, even if you had upgraded from rabbit ears to cable, there was still only a small portion of the available channels compared to today with a few hundred useless DirecTV. At first there was no "cable box" with remote; the coax just plugged into your antenna adapter. Funny thing to me is even though I have DirecTV, I still only watch about the same amount of channels as I would have with basic cable, not many more than the antenna days which we got around five clear channels.

My dislike of a rectangular screen runs so deep that I actually tried to convert my 1947 RCA 8T-243 set from one of the old fake rectangular viewing areas over a round tube to the "double D", but I never came up with the parts. Really, it would destroy any antiquity or value that the set has, but like most hobbies, I have learned that it's best to just enjoy what you have as opposed to worrying about what it is worth to a certain degree. In the case of the old 47 RCA, I would probably be hard pressed to get rid of the set for what the tubes and capacitors are worth. On a final note, I am glad that more interest is rising in 50s sets. I have always liked the space age look of those sets and often surprised at how little interest existed in them. I have found them at dumpsites more than anywhere else. Even though the CRTs are rectangular, they still possess a unique look I think, and many of them are far easier to work on than the 40s sets in my opinion. I must add that through all of my old color sets, the backup set was always my 56 Philco 21". The set still performs well today!

miniman82 03-20-2011 02:06 PM

Just a reminder..

:worthless

:worthless

:worthless

:worthless

:worthless

Tubejunke 03-20-2011 03:00 PM

Look man, I have addressed your perception and opinion ONCE! Here's a picture: :nono: When I get an email reminder showing this crap, all I see is how "worthless" my thread is to YOU! My advice would be to not view it if it bothers you so much that not everyone needs, or even has a way to produce pictures for you. This is not your thread, or your site, but you do have the right to your opinion. I took a few years out of my life to ensure that! I have been posting here for years; sometimes with, and other times without pictures, but I have always found people to be friendly and helpful no matter what. Can we please keep it that way?



Quote:

Originally Posted by miniman82 (Post 2998126)
Just a reminder..

:worthless

:worthless

:worthless

:worthless

:worthless


miniman82 03-20-2011 03:24 PM

I don't think this thread is worthless, I just really wanna see it! My intention was not to inflame, but obviously you perceived my post the wrong way.

Quote:

Originally Posted by Tubejunke (Post 2998129)
I took a few years out of my life to ensure that!


FYI, I still wear the uniform...

sampson159 03-20-2011 05:07 PM

relax.i want to see pics too.he will post when ready.gives us something to look forward too.

Tubejunke 03-20-2011 06:45 PM

Quote:

Originally Posted by miniman82 (Post 2998130)
I don't think this thread is worthless, I just really wanna see it! My intention was not to inflame, but obviously you perceived my post the wrong way!

Thank you Miniman, sorry if it seems like I went of the deep end, but as I stated before, I get email reminders in Outlook Express to tell me that someone has replied to my thread. When you post what plainly states, regardless of perception, that the thread is worthless without pictures; I get an email that states the following:

Here is the message that has just been posted:
***************
Just a reminder..

:worthless

:worthless

:worthless

:worthless

:worthless

So after a couple of those, I got aggravated as it looks much worse in the email than your actual post. Either way, it is what it is and it's behind us now. I have to get some NiCads for the camera and money is SUPER tight. That is why from time to time I post things that I wish I could sell. I am glad that people want to see what I have, but frankly I thought that such a set would be a pretty common visual, and initially I wasn't probing for technical information that might require a shot of some exact part or whatnot. Either way, thanks for the interest and I will do this as soon as I can. :thmbsp:

compucat 03-20-2011 07:29 PM

Quote:

Originally Posted by Tubejunke (Post 2998124)
That is exactly the way I am, and always have been. Actually, I think what started my interest in older TVs was seeing sets like this still in living rooms as a kid in the 70s and still as a young adult in the 80s. I remember thinking that they were, in some strange way, simply more interesting to look at; on or off! That interest led me to acquire a few of them at different times throughout the 80s. I would simply wander into one of the then plentiful TV repair shops where they would often have repaired sets that people had not come back to pay the bill on. Sometimes they would give me sets gladly to make room. Seems like I paid $10 for a nice remote RCA set that performed fine for a few years. Eventually the remote control section started acting up, so I just turned it off. Heck, even in the 80s having remote control was still a non-essential creature comfort and it really didn't matter. It was cool if you had it, and still OK if you didn't. Back then, even if you had upgraded from rabbit ears to cable, there was still only a small portion of the available channels compared to today with a few hundred useless DirecTV. At first there was no "cable box" with remote; the coax just plugged into your antenna adapter. Funny thing to me is even though I have DirecTV, I still only watch about the same amount of channels as I would have with basic cable, not many more than the antenna days which we got around five clear channels.

My dislike of a rectangular screen runs so deep that I actually tried to convert my 1947 RCA 8T-243 set from one of the old fake rectangular viewing areas over a round tube to the "double D", but I never came up with the parts. Really, it would destroy any antiquity or value that the set has, but like most hobbies, I have learned that it's best to just enjoy what you have as opposed to worrying about what it is worth to a certain degree. In the case of the old 47 RCA, I would probably be hard pressed to get rid of the set for what the tubes and capacitors are worth. On a final note, I am glad that more interest is rising in 50s sets. I have always liked the space age look of those sets and often surprised at how little interest existed in them. I have found them at dumpsites more than anywhere else. Even though the CRTs are rectangular, they still possess a unique look I think, and many of them are far easier to work on than the 40s sets in my opinion. I must add that through all of my old color sets, the backup set was always my 56 Philco 21". The set still performs well today!

I know what you mean about round tubes with rectangular masks. That has always bothered me too. If my set has a round tube, I want to show it off. I don't worry about the potential monetary value of my sets either. In fact, I purposely do not seek the particularly rare sets because I use mine frequently. I want something that was so popular that finding parts is no problem and I can use it every day without worrying about some unobtanium part going bad. If I had a CT-100 for example, I would most likely sell it rather than worry over the rare and delicate 15GP22.

I saw the color roundies and the 1950s sets still in use during the Seventies as well. I thought they looked great back then even with all the Sixties and Seventies stuff that was around which I also liked. Once the all black plastic cabinets became the norm, all I wanted were vintage sets from then on.

Tubejunke 03-24-2011 11:22 PM

2 Attachment(s)
Quote:

Originally Posted by miniman82 (Post 2998126)
Just a reminder..

:worthless

:worthless

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:worthless

OK folks, I'm going to try to upload a couple of shots. I found it necessary to take two to get the best portrayal of the set. I also thought that footage from the Woodstock festival in 1969 would be nice and colorful! :D:smoke: I hope this works and I hope everyone likes the set. I think this is a great example of a completely unrestored survivor!:thmbsp:

Tubejunke 03-24-2011 11:33 PM

OK! That worked rather well. It's no tall tale that these Zeniths produced a super rich color picture! I thought that I would note that it's really interesting just how far VOMs have come. That is my Hickok VTVOACM (vacuum tube volt, ohm, ampere, capacitance meter) as I like to call it, sitting on top of the Zenith 5111. It is the biggest meter that I have ever run into! Behind the Zenith is a 1948 RCA 8T-243 sitting on top of the 24" space Command that I am always bitching about. This color set coming to life might just mean the end of the Space Command. I just have too much stuff for one modest abode!

Sandy G 03-25-2011 12:10 AM

Glorious Lollipop Color...Ain't NOTHIN' quite like it ! (grin) These new sets w/their AFCs, AFTs, PDQs, all that other garbage just CAN'T really hold a candle to a good ol' Roundie in good shape & tweaked up properly...

miniman82 03-25-2011 01:16 AM

Looks great! Thanks for the pics!

Tubejunke 03-25-2011 01:11 PM

Quote:

Originally Posted by Sandy G (Post 2998583)
Glorious Lollipop Color...Ain't NOTHIN' quite like it ! (grin) These new sets w/their AFCs, AFTs, PDQs, all that other garbage just CAN'T really hold a candle to a good ol' Roundie in good shape & tweaked up properly...

Thanks! The GREAT thing here is that this set has not been tweaked, alligned, or otherwise! I replaced three tubes and wa-la. :thmbsp: WYSIWYG!! Supposedly, the family that gave it to the party that I got it from said that it worked when last used in the late 70's or early 80s. I guess the story was true! Admittedly, the color does not come in until several minutes of warm up time, but right now that is the only problem that I know of.

I think that the best thing to do is to keep the use light until I can afford to replace capacitors and/or other needed components so I don't fry a transformer or whatnot. Also, it's easier to restore a set that is already working then one riddled with problems like my 58 24" Space Command which now MUST find a home.

Tubejunke 03-25-2011 01:11 PM

Quote:

Originally Posted by miniman82 (Post 2998587)
Looks great! Thanks for the pics!

You are most welcome! :thmbsp:

compucat 03-25-2011 08:04 PM

That Zenith looks great. Now you've got me wanting to fix my Zenith roundie. It has been restored but something has gone reducing the vertical height and skewing the linearity.

Tubejunke 03-25-2011 08:38 PM

Quote:

Originally Posted by compucat (Post 2998656)
That Zenith looks great. Now you've got me wanting to fix my Zenith roundie. It has been restored but something has gone reducing the vertical height and skewing the linearity.

Thanks! What model/year do you have? I NEVER would have thought that this set would be any type of attention getter; especially with the metal cabinet, which I have been told makes it MORE special. Have you checked any tubes yet? Since your set is restored, I tend to think of tubes going as opposed to caps, but one never knows for sure I guess. The tubes I replaced to get my set working were not absolutely bad on a tester, but more marginal or weak. Maybe color sets like fresher tubes! LOL! :scratch2:

marty59 03-26-2011 02:29 PM

That's a nice set and a good looking CRT! Even though the metal cabinet sets were considered more "low line or utility" they were usually the first to get thrown out, junked, scratched, beat up, etc. It just seems that they've become more rare as survivors nowadays.

I'd be curious as to all the different color schemes that would have been available. Back in the seventies, I had a black ctc-12 and a silver/bronze color ctc-20.

I do recall seeing a black Zenith roundie in a bar setting once....

Tubejunke 04-01-2011 04:19 PM

Well folks, I guess the nearly inevitable had to happen sometime. The Zenith lost color all together. There is still a decent black and white picture though. I checked all of the color related tubes and video stages. All I found was a shorted 3rd Video IF tube; replacement made no difference. I already realize that a recap is needed in most old sets, but right now I just don't have the time for the complete job. I am pretty new to the color TV repair scene so any pointers will be welcome and appreciated. For now, I need to do a good visual inspection and some VOM checks underneath. I have already noticed that what is called a "horizontal efficiency" coil's plastic structure seems to be broken internally, but for now I see no horizontal issues; just no color.

Electronic M 04-01-2011 04:47 PM

Congrats on getting her going!

I'd make note of the settting of the color killer control, and then try tweaking it, that is how I fixed the no color problem on my 71' Zenith. If the level of the color signal droped, but not below the min necessary level it could cause the collor killer circuit to turn off the color circuits because it is not recieving the proper signal level, which can be fixed by readjusting the color killer control. Also if the color killer control is dirty or open the same problems could result.

It could be anything, but that is the first thing I'd check as it is usually the easiest thing to correct when bad.

Keep up the good work!

Tom C.

Tubejunke 04-01-2011 05:31 PM

Hi Tom! Yes, with little knowledge of color television circuits and the nature of their operation, I guess I can say that I am lucky that terms like chroma, R-Y/G-Y, and color killer sort of clue me in on key areas to look into. Last night I did try adjusting the color killer pot and could easily see that it definitely needs cleaning by its somewhat erratic reaction. However, no matter what adjustment I made I never saw an actual color picture. When I turned it up (or clockwise) I would get what I would call color bleeding into the black and white raster, so I turned it back down. I did notice that when I tune the fine tuning slightly off where a color signal would be present, there is what I would call a hum bar, or some type of interference present just left of center. This goes away if I tune away from where the color normally comes in. Perhaps a capacitor? I hope this makes sense! Like you said, "It could be anything." Thanks for the advice!

DaveWM 04-01-2011 07:02 PM

I would look in the color burst amp tubes. What ever you do, dont be tempted to started adjusting any coils. It was working fine so the coils did not suddenly jump out of tune.

miniman82 04-01-2011 10:22 PM

Some old sets need a tweak or they're never gonna work right, IMO. Both my CTC-7 and CTC-4 needed chroma alignments done (and done and done) till they worked correctly- remember that when you're replaceing parts like caps, the circuits they are in might need alignment after the recapping is done. That's because the caps you put in will invariably have a different value than the ones you took out, so it makes sense to have to make at least a few tweaks here or there. The CTC-4 in particular refused to receive a color program till I messed with the local oscilator, I guess it wasn't even running till I gave a certain coil a touch, and then it was off to the races. :)

DaveWM 04-01-2011 11:01 PM

Perhaps a tweeking of coils can help a set thats not perfect, but to go from working fine to zero color ,with nothing done in between, does not sound like spontanious slug movement.

I would stick with the basics until better knowledge has been aquired on what do to.

Start by wiggling tubes, then move on B+ checks, then plate and screen checks of the burst and chroma amp tubes.

My guess is a loose tube/bad tube/open power resistor (perhap taken out by a shorted tube).

ctc17 04-01-2011 11:30 PM

Let the set run for a few hours, does the color pop in? Try running the fine tuning up to the edge and see if you get the barber polling rainbow or if the color pops it.

One of the common things I run into is the color crystal will take a dump a few days after returning to service. Usually they lock in as they heat up.

Defiantly dont turn any cores. I have aligned several color sets and its not something you want to mess with unless you have the equipment and practice.

If you try the things Dave mentioned and you dont get anywhere I wouldnt hesitate to change the crystal. Just based on what I have seen with the 50 tube color sets I have.

One other thing to try.
let the set warm up good, make sure the color level is up, run the fine tuning up, now tweak the horizontal hold from one side to the other. till it looses lock on both sides. If color pops in or you get the floating rainbows while moving the horizontal hold its a fairly good indication the crystal has drifted.

Does the fine tuning even work? These are well noted for the fine tuning plastic gear cracking and not turning.

Phil Nelson 04-01-2011 11:55 PM

Quote:

Originally Posted by Tubejunke (Post 2999358)
Well folks, I guess the nearly inevitable had to happen sometime.

Not to be a spoilsport, but if you are still running it with 100% original capacitors, that is really tempting fate. That has the potential to be a beautiful performer, but if you burn up the flyback or power transformer, you will kick yourself. I would pull out the power plug until you save up enough to replace the electrolytic capacitors.

Just my $0.02.

Phil Nelson

ctc17 04-02-2011 12:12 AM

Not to start a war here.....the mid 60s tvs on are not like the old bw stuff. The electrolytics rarely go bad. Zenith used some superior quality parts.
You can actually diagnose these to a specific failed part rather that shotgun replace a group of parts.

Tubejunke 04-02-2011 01:17 AM

Quote:

Originally Posted by ctc17 (Post 2999426)
One other thing to try.
let the set warm up good, make sure the color level is up, run the fine tuning up, now tweak the horizontal hold from one side to the other. till it looses lock on both sides. If color pops in or you get the floating rainbows while moving the horizontal hold its a fairly good indication the crystal has drifted.

Does the fine tuning even work? These are well noted for the fine tuning plastic gear cracking and not turning.

WOW! :thmbsp: I have never gotten this much attention and advice about any set, but thanks to everyone just the same. This post will touch base on various comments and ideas given in the last few posts by different members. First, the fine tuner works just fine. Next, I checked all color related tubes and all three video stages. One of the first rules of troubleshooting is a good use of the senses and looking and sometimes moving things around a bit like tubes, wire connectors, and potentiometers, so I have pretty much covered the easiest but often overlooked possibilities. The visual inspection is why I mentioned the seemingly cracked spool of the horizontal efficiency (linearity?) coil, but I was not indicating that I would never start turning coil adjustments knowing that the set was working almost perfectly up to a point. I will say that I can't make the horizontal hold lose lock in both directions; only around 3/4 clockwise, but it locks steady. I don't want to elaborate too much on the fact that some small issues may lie in sections other than color producing sections so the focus for now remains getting color back.

I am thinking about this crystal that CTC-17 mentioned because from the get go the color took a few minutes of warm up time to come in, then it seemed stable. The last time it produced a color picture, nearly a half hour had passed and I was ready to give up for the evening when the nice color suddenly popped in. Last night I could not achieve any color other than some strange effects when I tweaked the color killer a bit. I just set it back where it was because again, adjusting a bunch of things that don't need adjusting would be ridiculous, but I am sure that a lot of people make that mistake.

I know that capacitors can be unpredictable in old sets, but frankly I have found more old paper foil capacitors to be problematic than electrolytics in my adventures with old 40s-50s black and white sets. So far all of the cans run nice and cool as does the power transformer, so for the moment I feel OK about the electrolytics, but I have not checked any of them. I only have a good Simpson analog meter for that which I know is not a "for sure" insurance that a capacitor is good or bad. Believe it or not, the main electronics supply house in this area has capacitors that are NOS and are probably nearly as old as the ones in this set. I don't see any paper caps underneath; only black or brownish non polarized "orange drop" types. I don't know how prone to failure those are.:scratch2: I know that this subject is always sort of up in the air; again I am trying to stay focused on color for now.

I have mentioned before in other posts that I owned a few color "roundies" as a kid for daily use just because I liked the way they looked and generally thought that the picture was better. Back then I did little or no repair on the color sets; my interests then and for years to come was primarily old black and white sets. So, I am more new to the vintage color TV operation and repair than to repair in general. I have been messing around with tube type radios and TVs for nearly 30 years. Admittedly, no formal training was involved other than one year of HS electronics until I was lucky enough to enter the electronics degree program at the local community college where I am to graduate in May. One of the things that I love about electronics is that you never stop learning! If you do, then pick up a Boolean Algebra book and start racking your brain with digital logic! :D Thanks to everyone for pitching in some opinions and ideas. It is great that there are sites like this where knowledge can be passed along that is not taught in any school! :thmbsp:

Phil Nelson 04-02-2011 01:32 AM

Quote:

Originally Posted by ctc17 (Post 2999430)
Not to start a war here.....the mid 60s tvs on are not like the old bw stuff. The electrolytics rarely go bad. Zenith used some superior quality parts.

I've found bad electrolytics in newer gear than that, but haven't worked on any 1960s Zenith sets, so I'll take your word that their parts are that good. Maybe I need to switch brands :)

I used to think that the brown/maroon "orange drop" types were pretty good, but not so much any more. This week I went back through an RCA CTC-11 that I restored a couple of years ago and replaced about ten of them. They had seemed fine at the time, but didn't hold up -- creating problems with vertical linearity and horizontal stability. Nothing is forever, I suppose.

Phil Nelson

DaveWM 04-02-2011 07:56 AM

Same here on zenith filter caps, more likely than not they are fine. I have worked on several zeniths from the early to late 1960's so far only one was a problem and it was open (the pincushion correction on a 23x). Not only have the cans been ok, but to my surprize even the singles have tested well. I use my cap tester on them to test at rated voltage for open and leakage, so far they test every bit as well as new caps! So I have revised my thinking these days to check them, if they test like new I leave them be. I do like to add fuses to the B+ and HOT, the B+ fuse will cover the PT and the HOT will cover the fly if the horz osc decides to stop. The HOT fuse is a little tricky, CTC-17 has done some testing and a reg fuse does not seem to work properlyt here, a chem fuse would be the way to go.

Prob the best advise would be to check the HOT current and work on it if too high. Also you can prolong the sets life by reducing the line voltage, this will take a large load off. the set should work fine at 110vac, around here its often at 125vac. I have not done it yet but a adj to the HOT screen value would prob be the best way to address the higher line voltage put out today


I would recommend ALWAYs changing the coupling cap to the HOT, esp if its a brown/maroon drop. Also the 1kv hard covered (white tube) foil caps that are generally found in the vertitcal circuit. Those seem to be bad about 50% ot the time (leaky) you will know if the picture seems to be jumpy vertically.

ctc17 04-02-2011 09:56 AM

Quote:

Originally Posted by Tubejunke (Post 2999438)
WOW! :

I am thinking about this crystal that CTC-17 mentioned because from the get go the color took a few minutes of warm up time to come in, then it seemed stable. The last time it produced a color picture, nearly a half hour had passed and I was ready to give up for the evening when the nice color suddenly popped in. Last night I could not achieve any color other than some strange effects when I tweaked the color killer a bit. I just set it back where it was because again, adjusting a bunch of things that don't need adjusting would be ridiculous, but I am sure that a lot of people make that mistake.

Yep, change the 3.58 crystal, its ok to use the small form factor one they sell in the blister pack at the local electronics store. Its a $2 part max. If you dont have such a thing locally I can send you one.


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