1970 Zenith b/w 23", 14N22 chassis - Videokarma.org TV - Video

Adam · #1 06-23-2009, 02:29 PM

This is the set that I keep near my bench to watch while I'm working on other sets. I picked it up 7 years ago on the curb, and used it as found, needing no repairs until now.

It developed some kind of buzzing in the audio, which I could hear even if the volume control was all the way down. I eventually noticed that adjusting the vert. hold would change the pitch of the sound, and also with the vert output tube removed, the buzzing went away all together. So I went about looking for some way that a signal from the vert oscillator could find it's way where it shouldn't be. But after fooling with the vert for several hours, and not fixing the problem, I found the trouble to be a bad electrolytic filter cap on the 215v B+ which feeds the audio output. While replacing this cap fixed the problem, I still don't understand how it could have caused it in the first place?

Also the vert output transformer makes a buzzing noise in itself, not very noticeable under normal operation, but it gets loud if you crank the vert size way up. Is the trans on its way out and should I start looking for a replacement, or is it ok like that? The vert works fine as it is.

Thirdly, in messing around with the vertical, I broke one of the pins on the socket (12 pin) for the 6FM7, I was able to solder it back together well enough to work, but I would like to replace the entire socket. Are these available anywhere?

While I have the bottom of the set off, I'm just going to do a complete recap of the electrolytics, figuring if one section of a can is bad, the rest may follow shortly. I don't think I ever posted a picture of this set, it's in the fake-woodgrained metal cabinet- I'll try and put up a picture later.

radiotvnut · #2 06-23-2009, 02:37 PM

It's been my experience that when a section of a canned electrolytic fails; the others are not far behind. Those sets are excellent performers when working. I have a console that uses that chassis and it still has a sharp picture. Turn it on almost every day. I'd like to see some pictures of your set.

Adam · #3 06-23-2009, 05:24 PM

Here's a picture of it as it sits right now, on it's side with the bottom plate off.
http://www.audiokarma.org/gallery/sh...ze=big&cat=503

compucat · #4 06-23-2009, 08:13 PM

That is a nice set. I would sell my granny to have any Zenith metal tabletop set. I have always liked the 1960s model b&w sets. That one deserves the best care and regular use afterwards.

Adam · #5 07-12-2009, 01:38 AM

I completely recapped the electrolytic and paper caps, and replaced the 6FM7 socket. I bought a new vertical output transformer to have as a spare, but didn't install it, as the original is still working good. The set works good again, I just have to pick up 2 really small bolts and nuts to hold the new socket in (I think this would be better than trying to re-rivet it), then I'll put it back together, and take a few pics of it running.

drh4683 · #6 07-12-2009, 01:42 PM

Those are as rare as table color sets! I only had one full sized metal b+w zenith, it was a '63 with space command. It didn't count as a local find though, it was bought on ebay and got completely destroyed in shipping thanks to a combination of UPS and the seller just wrapping cardboard around it calling it a box.

Never thought about it, but its rather ironic that I've found more zenith metal table color sets than B+W sets. You'd think it would be the other way around. That set you have is definitly a keeper.

peverett · #7 07-12-2009, 02:39 PM

I have a late 60s Zenith metal B&W set (23 inch, I think) that I have restored(and some others that I have not gotten around to yet). The picture is great using the RJtech converter box(+RF modulator) system that I am driving it with. However, there is some buzz in the sound. I suspect that the buzz would be much better if I were to use the Digital Stream converter box on it.

Adam · #8 07-16-2009, 01:32 PM

pictures:
http://www.audiokarma.org/gallery/sh...&size=big&cat=
http://www.audiokarma.org/gallery/sh...&size=big&cat=
http://www.audiokarma.org/gallery/sh...=5569&size=big
http://www.audiokarma.org/gallery/sh...=5571&size=big
http://www.audiokarma.org/gallery/sh...=5570&size=big

The volume/ on/off knob I have on there really looks like it belongs with this set, because it's fake wood-grained plastic with an aluminum insert, but it doesn't. It's actually off a late 70s Delco car radio.

*zenithfan1* · #9 07-16-2009, 09:05 PM

Looks great! I love these, I used to use my unrestored one as a daily watcher back when I was in an apartment and couldn't afford cable. I love that set still, needs caps now but still works. I think mines like a '66. Yours is in much nicer shape than mine. Keep that thing, I haven't come across another and I've searched. They are just about gone I think, like Doug said, the color ones pop up more often than these do.

drh4683 · #10 07-16-2009, 09:35 PM

Nice work, glad to see you chose the USA made sprague caps. You did it right!

I also notice the stamp under the chassis, United States Steel "USS". I always like when I get a set that has a chassis or cabinet steel stamping that happens to include the stamp from the steel maker. Its all on probability as the stamp is placed on the steel stock every few feet when its wound into the roll. You get lucky every now and then and get one like yours. Looks like the steel on yours came from Irvin works, which is in PA. That plant is still in operation too. Sometimes, you'll see the month-year code on the stamp, but looks like that is missing due to the punch outs on the chassis.

radiotvnut · #11 07-16-2009, 11:04 PM

Nice work! I guess I should re-cap my console; even though it works now. Over the past 20 years; I think I've only had 3 large screen metal cabinet Zenith B&W's. Two were '60's tube sets in beige metal cabinets. The third was a late '70's 23" solid state set in a woodgrain metal cabinet. I suspect those late '70's SS metal cabinet B&W's are very rare today.

Adam · #12 07-17-2009, 06:52 PM

Thanks. This set will continue to get a lot of use, as like I said before it's the set I keep near my bench and watch while I'm working on other sets. Actually I'm watching it right now, on ch3 using the original rabbit ears, receiving a signal transmitting from one of my B-T modulators.

That's interesting about the stamp under the chassis, I was wondering what that was. I do like to use the real sprague caps, but I don't use them all the time, I can't always find room for them under some chassis.

I'm not interested in too many solid state sets. But a B/W Zenith in a metal cabinet is one I would really like to find, particularly one of the earlier ss sets that still used the hand wired chassis.

radiotvnut · #13 07-17-2009, 09:01 PM

Quote:

Originally Posted by Adam

Thanks. This set will continue to get a lot of use, as like I said before it's the set I keep near my bench and watch while I'm working on other sets. Actually I'm watching it right now, on ch3 using the original rabbit ears, receiving a signal transmitting from one of my B-T modulators.

That's interesting about the stamp under the chassis, I was wondering what that was. I do like to use the real sprague caps, but I don't use them all the time, I can't always find room for them under some chassis.

I'm not interested in too many solid state sets. But a B/W Zenith in a metal cabinet is one I would really like to find, particularly one of the earlier ss sets that still used the hand wired chassis.

IIRC, the metal cabinet SS B&W that I had used a chassis similar to the one in my "new" 19" Zenith.

http://www.audiokarma.org/forums/sho...d.php?t=236612

If I knew now what I knew then, I'd have quite a collection of interesting TV's! Back then, TV's were just something for me to pick up, repair, and resell so I'd have some spending money. It seems like those old sets were common as dirt one minute and hard-to-find the next.

drh4683 · #14 07-17-2009, 09:17 PM

Yeah, orange drops especially I like to use whenever possible. Can't always use the lytics though. They're huge! Lots of times I have to use the chinese junk because of clearance/space concerns.

As for solid state handwired metal cabinet b/w: Rare as hell. I saw one once at a friends house sitting outside full of rust (was mint before he left it outside for 2 years). I thought it was a tube set but then saw solid state on the dial and was really surprised. I have quite a few service manuals for the 68 or so solid state b/w zeniths. They look neat.

The only solid state one I have is a royal 1290, which was a 12" portable zenith b/w from '65 with a densly packed point to point chassis. They are really rare too.

radiotvnut · #15 07-17-2009, 10:35 PM

Quote:

Originally Posted by radiotvnut

IIRC, the metal cabinet SS B&W that I had used a chassis similar to the one in my "new" 19" Zenith.

http://www.audiokarma.org/forums/sho...d.php?t=236612

If I knew now what I knew then, I'd have quite a collection of interesting TV's! Back then, TV's were just something for me to pick up, repair, and resell so I'd have some spending money. It seems like those old sets were common as dirt one minute and hard-to-find the next.

EDIT: Oops! That should have been "If I knew then what I know now, I'd have quite a collection of interesting TV's". Don't know what got into me! I guess I was thinking about old TV's too much!