*delurks* :)

Lots of interesting new TV scores from everyone lately.

I just had a nice score over the weekend. My one supervisor from my previous job sent me an email last week about this Zenith color console his mother-in-law wants to get rid of. It was mine for free.

I'm kind of excited as this is my first Zenith Chromacolor II. Now I see why everyone says how good those picture tubes are. 23", from August 1977. A little newer than what I was hoping for when he first told me about it, but still a pretty awesome TV. This is the first console I've had in 8 years as well.

I spent a couple hours Saturday working on it. It was barely watchable when I got it. Picture kept glitching, very out of focus, convergence needing realigned, background levels needed set, vertical height was shrunk, etc.
I reseated every module in the TV, which took care of the majority of the problems. Then I had to touch up all the vertical size, convergence, greyscale, and focus.

One thing is, when I first turned it on, it wasn't very bright. Focus was marginal. I adjusted focus, and I got it to its proper position, which still wasn't very sharp. After letting the TV play all day, the tube woke up and got nice and bright and sharp.

All that's currently wrong with it is the pilot lamp behind the tuner is burned out, and when you turn the Color Sentry button on, it dims the picture almost all the way on the contrast. For now I'll just leave it that feature off until I get another chance to work on it.

She also had all the paperwork, including the original tags that were on the front of the TV, and all the manuals and tuner number inserts. If anyone is interested in seeing those, I can put them up online, but I left the pictures full resolution and put them into a pdf file, so it is rather large.

Also, while fooling around, I had my camera out and recorded it. I was playing mostly early-mid 80s commercials I put on DVD from Beta most of the day, and some other odd stuff. Video (http://home.comcast.net/~tv_beta_guy/zenith2.avi) The first part of the video was when I had my laptop hooked to the TV. It was this subtitled Japanese anime Kaiketsu Zorori I downloaded. I left it in this video as it really shows how good of a picture this set has. The latter part was recorded around Christmas of '86 on CBS I had on Beta.

Nice job! They do have a sweet picture. If your focus continues to degrade even with the control maxed out, the trippler unit is most likely at fault. I got one from MCM electronics for about 30 bucks. ECG-526a or equivelant. It really improved the picture, and is a drop in replacement for the original.

The focus and just overall brightness has actually improved a great deal since using the set, and has been getting better. The tube is slightly weak. I don't have a tester, but when you crank the contrast on maximum (which is way too bright for normal viewing anyhow) the red and green guns bleed a little bit. Adjusted for normal viewing things look excellent :)

I don't know how long this TV sat before I turned it on.

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No zoom or remote on this TV. It does however just have single knob tuning with 6 UHF presets.

I had the dial off in those pictures, as I was polishing it up. I need to locate another knob for it, as this one is broken.

Mike, if you can send me a picture of the knob, I may have a replacement you can use. I've got tons of zenith tuner knobs from the 70s.

000

The tuner shaft is fine, but the knob for it is cracked and is held together by tape. The inside that slips onto the shaft has crumbled to nothing.

Jordan: I'll get a picture after I get home today... and thx :)

Sigh. . . .

I really miss working on those sets.

SWEET SET!!! I've got a 23" console as well. Mine is from 1975. You can use an alignment tool to adjust the controls with the color sentry turned on. You just insert in the middle of each user control shaft (brightness,contrast,color, etc...) I'd keep an eye on that tripler tho. The set should not have been drifting out of focus, and I've never seen a bad (or even weak) chromacolor delta tube. If that tripler is going bad, it would cause lower high-voltage which would effect focus and brightness. Have you used a high-voltage probe to check the readings?

Hmmm... I don't have an HV probe to check. The focus isn't drifting... I had the setting dead on. It only happened when I first turned the TV on. It just wouldn't focus fully when I got it to its best setting. It's been fine after Saturday. Really sharp.

So I guess it would be advisable to get a new tripler then?

And thanks for telling me where the controls where at for the Color Sentry. I didn't bother looking for them yet. I remember seeing them on much later model Zeniths where you could see the actual holes in the control panel. Didn't know they were behind the user controls like that.

(on the focus issue) I've had problems with the CRT sockets on those, especially if the TV was ever in a humid climate. Pull the socket and see if there's any green corrosion or powder on the focus pin (heaviest wire that goes to the CRT pin all by itsself in the side of the socket). If so, then clean the pin and possibly replace the socket. If it looks clean to begin with, and you can't smell the ozone odor or hear any arcing in the CRT socket, that might not be the problem afterall. There are other parts in the focus circuit too, and frankly I don't remember the tripler often being the cause of focus problems much. Definitely a possibility, but 9 of 10 times it was the CRT socket or something loose or arcing in the wiring and connections between the tripler and the CRT. I probably have a used 526A tripler someplace that I could give you, so you wouldn't have to buy a new one on chance. Can't promise though, because I haven't looked in that box lately. But let me know if you think you need one, and I'll look.

Charles
motocrossKXrider@yahoo.com

Charles

There wasn't any corrosion on the pins that I can remember.

All that happened was, when I first got the TV, the picture wasn't as bright as it should be, and the focus control was dead on for good focus, but wasn't very sharp.

After I cleaned the set, reseated all the modules, etc. I let the TV play for several hours. The tube got brighter and the focus became razor sharp. It's been fine since.

Now that it was mentioned about never seeing Chromacolor II tubes being bad, that has me curious. The tube is still nice and bright, just when you crank the contrast on maximum, the red and green guns bleed a bit. When adjusted for normal viewing, it's fine, and still bright and sharp.
The only thing I could think of is the tube is a bit weak (I have no way to test it) and it just needed to wake up. I've had a couple other TVs behave the same way when I first got them.

Or is a component failing? It looks great as is right now, and works perfectly. I have no clue how much use this TV has had and how long it sat prior to me getting it.

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I knew it had to do with saturating the drive transistors.

My mistake was just that I've always associated it with a weak CRT. I have compensated for it on some TVs by adjusting the screen voltage, which would fix that problem if the screen voltage wasn't set correctly to begin with.
I have 2 TVs like that. One is a 1981 RCA XL-100, but it is obvious the blue gun is weak, since I have to turn the R and G drives all the way down to get a proper greyscale.
The other is a 1997 GE 27" I use as my daily watcher. I'm not the original owner. It was given to me last year, as it had the common tuner shield problem which I fixed. I remember seeing that TV 6 years ago, and the red gun was bleeding. But this TV was on almost 24/7. I redid greyscale on it for the previous owners and while doing that, readjusted the screen voltage using the setup line, which cured that problem and gave a much sharper image.

I'll just have to see what the deal is with this Chromacolor II. I already readjusted the screen voltages. It was actually set a bit high. Using the setup line cured that and got a nice background greyscale. Truthfully the TV looks great. Maxing the contrast out just causes it to bleed, but by then it is already way to bright anyhow. I don't remember seeing a subcontrast adj. but then again I didn't go looking for one either. I found a subbrightness/bright limiter, but that's it.