I started recently collecting TV's again, and this past week came across a Zenith 14CC16 hybrid chassis, my first delta gun find. Everything on this set seems to work except the tuner, as I get a raster but no video or sound, no snow either, doesn't matter if I try VHF or UHF. I would like to fix this set myself since it's a rather nice old set in my eyes, has the point to point wiring, and it seems the CRT is in pretty good condition!

Where should I start with this set, to get the tuner to work (if that's the problem)? I am suspecting maybe one of the tubes on the VHF tuner is bad, but I have no way of testing that (don't own a tube tester), but I found the tubes for cheap, however would like any suggestions before I just start throwing parts at it.

One more thing, is there a way to get a video signal into this thing past the tuner?

Here is a picture of it's current state:

Nice TV! Tuner tubes usually last a long time. Good luck with it.

I would start with the tuner tubes then on to the I.F section. Check the tubes there if there is any, I think there is, I have a similar set. Also, check the tube sockets in the I.F and tuner, sometimes they need a spritz of de-oxit to take care of intermittents. Have you tried wiggling any of those tubes? You really need a tube tester, one that checks for grid leakage would be the best but any would do for now. You can use a tuner subber to inject a signal into the I.F section if you can get your hands on one.

I did wiggle and remove and reinstall both those tuner tubes, and I also tapped around that area of the chassis to see if I could get any response, but no luck as of yet.

I forgot to mention the set has a few Zenith tubes, but most of them are Sylvania tubes, which leads me to believe some of the tubes were replaced at one time. Both the tuner tubes are Sylvania. I think the IF may have a transistor in it, when I open the set next I will check that area, and I will also get some of that de-oxit, also this weekend when I make my rounds looking for old junk I will sort through all the NOS tubes at my regular junk store and see if they have any I may be able to substitute.

Thanks for the quick replies and help so far, this is an excellent forum!:D

Hope you get 'er fixed, post a pic of the inside and I may be able to help you more. The Zenith guru, Doug {drh4683} may chime in at some point too. Those tuner tubes were probably replaced by someone else trying to fix the problem you are having. They probably just put the set away after that for a "just incase" tv as they were quite expensive and people didn't throw stuff out like they do now.

I shall post pics of the insides and the inside service label after I get out of my plumbing class.

The last thing I want to do is chuck this beauty, especially since the picture tube seems to be strong.

BTW I found this set at the same junk store that has boxes and boxes of tubes, it was destined to be chopped up and scrapped for the metal but I saved it!

If those tubes are cheap, grab as many as you can!

Video blanking caused by service switch failure? When you change channels, do you get a flicker of any type in the raster? Check all tuner connections as well.

Thats a nice TV. Ive had quite a few of those over the years. Ive had a few too that had the blank raster no audio issue as well. Certinaly check the IF lead in cable to the IF sub chassis. Sometimes those go intermittent, just plug it in and out of the sub chassis to see if anything happens. The IF sub chassis is the large rectangular metal case with the cover on it, mounted to the chassis via three 1/4" hex screws. Since this TV has AFC, it will plug into a socket with two prongs. You will need to pull the wires off of the chassis though if you need to remove it (all the wires plug into the side, there are either 4 or 5 of them). First thing I would do is check the +24 VDC supply voltage at the IF chassis. It should be a brown/white wire. If its missing or low, the power supply is at fault. Also check the 6MV8 sound/AGC tube too. Thats about the only tube that can cause this kind of trouble in this TV. The fact that you get nothing (no snow) even on UHF pretty much clears the tuners of any trouble. If you had snow on UHF, then the VHF tuner would be suspect.
If all fails, suspect a faulty 180-162 IF sub chassis. Ive had it happen numerous times, so don't be surprized if its bad. The sub chassis was like a module, it was designed for simple replacment, return to zenith for a rebuild. If its bad, you'll need to do some troubleshooting in there, either a faulty transistor or diode someplace. I really enjoy working on these little hybrid zenith portables. If you live in chicagoland, I'd like to check it out and help get it going again. The picture on those little sets are great when working right.

Thanks drh4683! I'm gonna try the simple stuff first, like the leads going to the IF module, and the possible suspect tube.

Here's pics of the inside!

Start simple, clean it all up inside with canned air and/or a small brush, then use DeOxit or high-grade isopropyl and a pipecleaner on all the tube sockets. You'll be better off even if it doesn't fix anything. Also, it's a good idea to clean the rectifier tube and anode cap....these areas can be troublesome in the future.

I'd start with the 4GY7 and 2HA5 first then check the others...... Good luck

So far the 24VDC to the IF module checks out, the cable from tuner to IF seems to be good, and I removed and reinstalled the 6MV8. I need to get some cleaners and canned air when I have a chance to clean this thing all up. Will keep you guys updated, and thanks for the help so far!

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