Seeking advice on a found Chromacolor I
 

Hello All,
I'll start off by saying that I am a newbie here, and although I am a student of electrical engineering, I will readily admit that I have relatively little knowledge about what I am working with here.

I recently came across an old 16" Zenith Chromacolor at a local tech dump, and I figured it would be a good idea to run it past some folks with a bit of knowledge on the subject of vintage televisions before something potentially worth saving got trashed. If it is a set of any value, my eventual goal is to test the set to see if it is still working and then work to find a home for it.

In terms of initial impressions, I would be tempted to say that the condition was decent, were it not for some strong indications that it came from a smoking environment. That said, looking in back, all the parts and original tubes seem to be there, so I would give it a reasonable chance that there is still some life left in it. I plan on putting it up on a variac and giving it a slow start up over the weekend. Assuming I can get it to at least turn on, though, how would you folks recommend I test the picture/reception? Are there any analog stations that I might be able to pick up these days?

Furthermore, regardless of whether I can get it working, is it even worth saving at all, even for parts? Basically speaking, what should I do with this now that I have it? Sadly, although the history and design of old tech fascinates me, I really don't have the room to hold onto something like this, so unless I can find a suitable home for it, I will be forced to take it back to the dump.

Any information or advice you might be able to give me, no matter how basic it might seem, would be greatly appreciated. Especially with regards to testing, any advice you might be able to give so that I can minimize the risk of damaging the set would be invaluable.

http://i1084.photobucket.com/albums/...ps006490ad.jpg

http://i1084.photobucket.com/albums/...ps4efdb6f4.jpg

http://i1084.photobucket.com/albums/...ps9bc0a9c1.jpg

Hello and welcome to VK!

That is a very cool find, color portables from this era are hard to find in good condition.
What size screen is it? can't tell perspective from the Photo but I'm guessing 14"-15"?
It's new enough that I would probably just plug it in and see if it works, watching closely for smoke.

Since you have a Variac available to you then that would be a wiser choice but you don't need to spend the whole weekend bringing it up, 30 minutes would be more than enough. I monitor the amperage as I ramp up the voltage and as long as it stays below an amp or two I just keep cranking it up until I hit 115.

Being a Zenith from the 60's I would guess it'll at least turn on and give a raster.

Please don't return it to the dump, if you decide you don't want it I have no doubt someone here would be happy to take it off your hands!

Eric,
Thanks for the quick reply. It is a 16" screen. I wasn't actually planning on taking the entire weekend to bring it up so much as I was stating that the weekend was when I would have time to do it. I'll probably ramp it up over an hour or two, just to be safe.

If this is something that people might want, though, I will definitely consider passing it along to one of the members here at some future date. The entire reason I pulled it out was on the hope that someone might want it.

Nice find and I think this one is from around '73-'74. If it were mine, I'd fire it up at full line voltage. Being a Zenith, it could very well still work just fine.

Welcome from a fellow EE student.

I've got one of the CCI consoles running right now, and it has been a daily driver set for around 5 years. They are great sets, well worth saving from the dump. There is not a whole lot of collector value for them though. You can probably get 10-50$ for it depending on condition, who wants it and who is close.

As for signals there are options. There may be analog LP stations near you, but if not DTV converter boxes, cable/sat boxes with RF outputs, VCRs, DVD players and older video game consoles all are potential signal sources for your set.

If no body else steps up to the plate I might just give that set a home(I have a big soft spot for Zenith products).

BTW what is the set next to it?

Be a shame to dump it, portables seem to be rare probably
cause there easy to get rid of. Also this one is a chromacolor CRT
& has high focus voltage like large sets. Probably a C or D
line set, apx 72-73. Replaced by a 17" solid state in '74.

73 Zeno:smoke:

its a zenith so its plug and play!those were some fine sets and the picture was always the best in class.great find

being a zenith portable from the 1960's makes it rare, I have not seen one locally in years. You should have no problem finding a home for it from someone here.

...

That's the back cover from the set! :yes:
I have one like it in my stash. IIRC, it originally came from Doug. :thmbsp:

Not being an EE but a broadcaster for 44 years it might be educational to see what came before current EE thinking in this small plastic box full of lead solder, glass enclosed amplifiers just above the diode level, RF signals that magically become analog voltage signals, the division of those signals to sound and picture, a brute force voltage via capicitance to make an electron beam, the ratios of time and frequency to make a scanned picture in a particular ratio, color suddenly worms it's way in to the signal, and a view of it's little place in American design. A great well-rounded education on television...then, not now.

Please keep it and learn from it. It ain't that big. We all have worse problems with our wooden box console sets. You are already most of the way there with the screen name of Diode which is already friendly to us and we are in your corner. And we are looking for an EE to make our miserable flat-screens better. Back to the basics?

An update on the set: I cranked it up on a variac over the course of a couple hours and it seems to be working great.

Sadly, unable to pick up any analog stations, and lacking anything that outputs analog video at RF, all I was able to display was snow. (it doesn't have an F-connector, so I am not exactly sure how I would input it anyway, except to maybe strap an antenna to the video source somehow). I am considering making some kind of frequency modulated transmitter and using an RCA output as the modulation signal so as to get a video signal to the antenna, but perhaps there is some easier solution I am missing here?

http://i1084.photobucket.com/albums/...psd6c91ee2.jpg

wally world and radio shack both sell cheap RF modulators that can take a composite video signal and output to channel 3 or 4. Then you need an composite video source, most DVD player still have that (video, audio L and R).

Or if you can find an older DVD player they had the RF out again to 3 and 4, thrift stores often have them for 5-10$

Or you can use one of the digital boxes sold during the change to digital (think it was 2009). Ebay/cragslist and may even still find them at places like radio shack, but not cheap (50$+ IIRC). These were often poorly made so I would not spend a lot of money on one. with these you need some kind of antenna, a cheap rabbit ears will work if you are near a large city.

you need a balun to convert from 300ohm to 75ohm (I am presuming the set has a 300ohm antenna connection) and some coax to hook up from what ever the device used to the set.

Baluns of the type needed to connect the set to coax can be had at radio shack for ~5$.

I have one of these, but mine is the remote control version. I got it in about 1994 and have used it ever since... Mine was made in 1973. I love the TV, it makes an excellent picture, and if I had to get rid of all of my televisions except for one, this would be the one I would keep! It responds well to a decent RF modulator and a signal from a DVD. The tubes in the tuner can be replaced if the picture is a bit fuzzy. Once you get a signal to it the condition can be evaluated. I am also an EE, I picked up my Zenith as a young teen and it taught me a lot about how TV works. I watch it daily.

Don't bother to make an RF modulator - too hard considering you can buy one at radio shack

http://www.radioshack.com/product/in...ductId=2103095

The "balun" you need to put a signal to the input is this

http://www.radioshack.com/product/in...ductId=2062049

Get a short length of coax as a jumper between the modulator and the balun, connect the balun to the "VHF" terminals, set the TV to channel 3 or 4, and feed a composite video and line level audio signal into your RF modulator.

For now don't put a lot of effort into cleaning the chassis beside using a vacuum with a soft brush to get the dust out. I have had good luck cleaning plastic with aerosol microwave oven cleaner, and the screen of course can be cleaned with windex.

GOOD LUCK and hope you keep it, someone needs to hold the torch for the old TV hobby heading into the future. also this is a "hot chassis" TV, so be sure to read up on what that means and how to deal with it before attempting to operate it without the back cover!