How to connect Zenith. - Videokarma.org TV - Video

Uly235 · #1 03-07-2010, 04:26 PM

I recently bought a black and white, Zenith. I attached pics of the back, can anyone tell me how to connect things to it from the back, like dvd player? Its had not uhf or vhf, so I am confused how it connects.

David Roper · #2 03-07-2010, 04:34 PM

You will need an RF modulator to run it from a DVD player. The DVD's A/V cables connect to the modulator, which in turn connects to the TV with a coaxial cable. You'll need a matching transformer to connect the RF cable to the two antenna terminals on the set.

These vintage TVs have no direct video inputs.

You can use it on analog cable however, or digital cable fed from a converter box. You'll still need a matching transformer for the antenna connection though.

Wait--before you start connecting anything to anything--is it restored? If it's been sitting unused for 40 years, don't expect it to just take off and work. Not for long anyway.

Uly235 · #3 03-07-2010, 04:43 PM

Its has not been restored, it has been sitting around for a while. Is that important?

David Roper · #4 03-07-2010, 04:55 PM

Yes, very. It is full of 55-year-old paper and electrolytic capacitors that all must be changed for it to work safely even if it seems to work properly, which isn't likely. There are probably lots of out-of-tolerance resistors that should be changed. Tubes are usually the least of your worries, but there may be a couple of weak ones. You can't find them without testing them.

David Roper · #5 03-07-2010, 05:02 PM

Does it look like this?

Uly235 · #6 03-07-2010, 05:04 PM

Yeah, it looks exactly like that one. It turns on fine, but no picture cause i need a rf modulator i guess.

Uly235 · #7 03-07-2010, 05:05 PM

I am currently cleaning it and all the tubes, I see some tags showing that it has been serviced before. Not sure how long ago

David Roper · #8 03-07-2010, 05:12 PM

It is up to you if you want to run it as is. Mine was trying very hard to work before I replaced anything other than a fuse, but the picture was stretched vertically and would shrink and fade after just a few minutes. Yours very well might have similar vertical distortion that isn't apparent without a signal. Incidentally, your TV does have VHF, but it's VHF only. Nowadays with over-the-air TV gone digital it doesn't matter that there's no UHF. Whichever type of converter or modulator you connect to it will have to output an analog signal for one of the VHF channels, almost always 3 or 4.

My recommendation would be to replace electrolytics and any of the paper caps that block high DC voltage at a minimum. My thinking is if you're under there to do any of them you should do them all. Have you worked on any type of electronic gear before? Do you have a soldering station?

Uly235 · #9 03-07-2010, 05:19 PM

So i have to get a converter or modulator for VHF only, and tv sets only to channel 3 or 4. I have not worked on any electronic gear before. I dont have a soldering station either....

Uly235 · #10 03-07-2010, 05:21 PM

What modulator or converter would you suggest?

David Roper · #11 03-07-2010, 05:27 PM

What's your general location?

The TV will work with any type of converter that is designed to allow analog TV to receive digital channels. That goes for both broadcast and cable converters. But to connect a DVD, yes, an RF modulator is necessary since DVD players only output line-level video and audio and the TV has no jacks for that.

Just please keep in mind that catastrophic failure can result from running the TV unrestored. A failure of an easily replaced small part triggers a chain reaction that can damage bigger, less commonly available (and more expensive) parts like a power transformer.

David Roper · #12 03-07-2010, 05:29 PM

I bought my modulator at Radio Shack. That was about 5 years ago though; I kind of doubt they still carry them. Hmmm...let me Google....

Uly235 · #13 03-07-2010, 05:30 PM

I am in california. What should I replace and how should i do it?

David Roper · #14 03-07-2010, 05:42 PM

The RCA CRF 907 looks like a decent little unit, at least the reviews are positive and it can be had for under $10.

This TV isn't difficult to restore once you have some experience, but I absolutely recommend not tackling it as your first project. There are a number of collectors/restorers in California, maybe one nearby who can help get you started. You will need a soldering station and solder (of course) and something to practice on. Maybe you have a small old tube-type table radio? Those are good to practice on for acquiring both soldering skill and the ability to read a schematic. That's another thing you'll need btw, the schematic for this set. I learned how to do this all from scratch...but it takes time.

I think you're probably getting an idea of the scope of the project!

Phil Nelson · #15 03-07-2010, 05:43 PM

Let me repeat David's friendly advice that you should replace the old capacitors (especially electrolytics) before expecting the TV to play without the risk of damaging itself. These articles give you an idea what's generally involved in getting old TVs to work.

http://www.antiqueradio.org/RCAT-100Television.htm

http://www.antiqueradio.org/DuMontRA-103Television.htm

In the first article, note the section about replacing capacitors. This article has more info on that topic.

http://www.antiqueradio.org/recap.htm

If you do it right, you may be able to make your old TV play well and give you enjoyment for a long time. You usually can't expect to reach that point just by replacing a couple of tubes and blowing off the dust. It's more like finding a 50-year old car in a barn. You wouldn't expect to just top off the gas tank and speed away on a long trip.

If you have never done anything like soldering, I'd recommend buying a cheap old tube radio at a thrift store and practicing on that first. TVs are not good beginner projects. (Among other things, the high voltage can kill you.)

Phil Nelson