Zenith 19L25 Chassis ( Service Info )
 

I've been thinking that when I get done with my Admiral, I want to take a crack at recapping that Zenith television set. It's a 1953 model L1846R with the 19L25 chassis. There's a member here at VK that posted a long time back that he had some service manuals, including this one that he'd be scanning into PDF format but I haven't been able to get ahold of him. I was wondering if anyone might have a copy somewhere I could get a look at because I haven't found any on the web and I can't exactly afford to order a set right now...

Update: I did find that I can get the schematic from Sam's with a subscription. Might be worth looking into, since I may be working on more things like this over time.

I also found out what type of CRT I've got here. It's a 17LP4. I'd like to remove it from the chassis because it weighs the thing down horrendously and I don't think I'm gonna be able to do much work on it until I do. There's a bunch of wires running to terminals which then run to the yoke which is held within a metal bracket. It's held down with about 4 screws, but it looks like I'm supposed to desolder the wires to free everything up.

Don't ask me why I included a picture of the 1B3GT. I thought it was purty.

Why would you want to un-solder the yoke?... on most of these old sets,one can slide the CRT out and leave the yoke mounted on the chassis. Am I missing something here?:scratch2:
jr

Ohhh yeah... so all I should really worry about is taking off is those magnet rings in the back and that ion trap and slide it out from the front?

Wow, I just got it out in no time. That was a lot more simple than it looked... thanks!

Do you have service info yet? I just picked up a stack of Rider's manuals today, and the complete service info on your set is here...

FWIW, I have a 10" tube with even bigger cracks on the neck. I put it into my dad's tv and he has been playing it nonstop for the last month or so-still runs good. I would at least use the old crt to set up your tv during restoration. Maybe hunt down a brightener if the picture is still dim after a recap...

Yeah, I'm pretty sure this CRT will do well-enough for me to check for improvement after I replace the capacitors. If there's hope for it, even with the cracks, then I might not count it out just yet. It had a dim picture that whole time and when I saw the crack around the neck, I'd feared the worst.

Oh, and I haven't gotten ANY kind of service info, yet! The whole reason I was taking out my CRT today was to get into the chassis and make a lame attempt to find the values on the capacitors themselves. The cap's don't look melted like the one's in my radios, but all the same. But yeah, if you were able to get that service information to me somehow or another, I would definitely appreciate it!

Sounds good. Pm me your shipping info and I'll get a copy made for you. If it is a slow day at work tomorrow, I might get the chance to go over the parts list and be able to tell you what caps would need to leave that set.

While I'm getting things sorted out, I thought I'd take a moment and talk about another interesting feature of my Zenith. It's probably not that uncommon for televisions of this vintage, but it's just something I had never seen before!

http://img831.imageshack.us/img831/4797/channelknob.jpg

This never actually worked the few times that I did turn on my tv, but got the idea of how this worked using a LED light on my keychain. To make it project the numerals properly, I'll have to do some adjusting. It had a type 47 bulb in there, which seems to work when I power it with a 9-volt battery. I never saw it light while in the television, however.

I wonder why it displays the number "25" when turned to channel "13" ...

http://www.videokarma.org/attachment...3&d=1279406118

I could be wrong on this particular TV set, but usually there's a plastic cap of sorts that would cover the terminals on the yoke, and also hold the centering magnetic rings. But the plastic used does decay, so it's not surprising that it's missing here. And the ion trap is way too far back on the neck.

You're right-the back cap of the yoke has rotted away, but luckily the centering rings are still there-rattling loose around the ion trap. I don't know what the "25" numeral is about-does this set have a UHF function?

Also your tube has a really neat label on it-what does it say?

I'm sure my set probably has UHF in there somewhere. It has a lot of interesting attachment plugs for various things such as a remote control of some sort, and also "Phonevision" which was the world's first pay-per-view system, exclusively from Zenith:

http://en.wikipedia.org/wiki/Phonevision

A great deal of that black plastic stuff has deteriorated throughout my set, especially around the yoke there and also around the back of the picture mask which resulted in little annoying crumbs of plastic falling between the face of the CRT and the glass. There were shards of black plastic everywhere in that set when I first got it, along with flakes of aquadag that fell off the CRT.

I had the ion trap moved back in an effort to fill out the picture which was leaving the bottom quarter of the screen black, which did help but I gave up knowing full well there was more to it than that. I'd like to figure out something I can put over the back of the yoke in place of that plastic stuff. I wouldn't mind getting that stuff out of there completely, especially around the picture mask.

Anyways, here's a look at the labels around my old CRT:

http://img842.imageshack.us/img842/6971/img0912.jpg

http://img832.imageshack.us/img832/9242/img0915.jpg

http://img837.imageshack.us/img837/1240/img0916.jpg

http://img842.imageshack.us/img842/177/img0914p.jpg

Oh... and check out these rather colorful plastic pieces that support the CRT:

http://img832.imageshack.us/img832/2298/img0918p.jpg

When I first took this thing apart, I seriously thought those looked like they were made out of marble or something...

Your ion trap is probably pushed back like that because your centering rings are screwing things up. They should be pushed flush up against the back of the yoke. Doing so and adjusting the ion trap for max brightness might give you a much better picture.

When I had this all together and I tried to get a picture on it, I recall that I had the centering rings all the way forward and I still could not get a good picture. I moved the ion trap back just a hair and found that it filled out the screen like I wanted, although I still had a small black spot in the top right and left corners. Before I did that, the image would even overlap itself at the bottom, and in general was slanted to the right. Everything was just streaming from right to left, completely unwatchable. The closest I ever came was when I had a John Wayne movie playing on the VCR and I could make out the characters in the movie, but they were scrolling up and down and sliding off into infinity towards the top right corner of the screen. No adjustment on the front panel improved this, so I gave up before I ran the set too long and fried something.

Greetings from FixitLand!

Now THAT is interesting! First thing I noticed in your picture is that the channel numbers aren't in numeric order; the same thing is done on my Zenith (K1846R "Stafford", chassis 19K20) which appears to be the previous year version of yours. But that ghost-like number is truly strange. Don't think my set has that feature. But it could be that your set, like mine, has a UHF "strip" in the tuner. On my set, it was installed in place of Channel 3 (so I don't have Channel 3 available!). Perhaps such a thing was done to your set? Very curious! I've gotta check my set a little closer...

Take care,
--
J. E. Knox 'The Victor Freak'

odd. It looks like another number off to the left? I wonder if it's just set for 25 on 13 or if it is the whole uhf band that displays thru the center. If so there must be some way of rotating the uhf display.