View Full Version : Help with Zenith B&W


dsndblm
07-31-2019, 02:37 PM
Hi all,

I have a Zenith TV that I'd like to get working correctly. I haven't had any luck with info or a schematic. There's a number on the chassis, 13A16.

I remember going with my Dad to buy the TV as a young kid. I couldn't remember much more than that. I looked at the date codes on the tubes last night and all but two tubes are Zenith branded, have 1970 date codes on them. Point to point wiring and a nice strong steel chassis. This was our family TV until sometime in 1976 when we got a larger color set. The Zenith was used in kids bedrooms, then at my house in our spare room until it was retired about 2005. It still works but needs some help. The tubes that I was able to test on my TV 7 and B&K 700 were all marginal. Some of the tubes are higher filament voltage compactrons that neither testers sheets contain the tube settings.

This TV always had a really sharp nice picture for a black and white TV. Now the outer edges of the picture are blurry. The multi section electrolytic has low ESR. I see some black spraque caps that might be suspect.

I'm a tube radio and tube hi fi guy. Have done scratch builds and several complete restorations. I know zip about this TV but would like to learn. Any help would be greatly appreciated!

Thanks

zeno
07-31-2019, 03:46 PM
The chassis number is good. It is listed as Sams 1076-3.
DO NOT buy the Sams for $22, thats a last resort. As far as repairs
go start with the most major one. Dont blindly recap or replace
tubes that check weak. Most old Zeniths come to life & work
fine with questionable parts. Its just the way they are.
Best is to post a pix showing the symptom. True content from a
VCR or DVD are best. Test patterns can also help sometimes.

73 Zeno:smoke:
LFOD !

dsndblm
07-31-2019, 06:00 PM
Thanks for the advice. I'm cleaning it up, will power up and report back. Thanks!

dieseljeep
08-01-2019, 09:54 AM
The chassis number is good. It is listed as Sams 1076-3.
DO NOT buy the Sams for $22, thats a last resort. As far as repairs
go start with the most major one. Dont blindly recap or replace
tubes that check weak. Most old Zeniths come to life & work
fine with questionable parts. Its just the way they are.
Best is to post a pix showing the symptom. True content from a
VCR or DVD are best. Test patterns can also help sometimes.

73 Zeno:smoke:
LFOD !

I'd be more concerned about the CRT after all those years. The set has that real skinny neck CRT that didn't seem to last like the others. :sigh:

dsndblm
08-01-2019, 02:55 PM
So, last night I powered up the old Zenith over a couple of hours using a variac. The old girl did fine, screen is bright, no issues. I took the set in the house and realized that I don't have one device that I can use to drive the audio or video. I ordered a RCA compact modulator from Amazon that I think will allow me to use the rca out from my dvr, into a coax that hooks to an adapter, then attaches to the screw input terminals on the back of the set. Will report back when the device arrives.

dsndblm
08-03-2019, 10:29 PM
The chassis number is good. It is listed as Sams 1076-3.
DO NOT buy the Sams for $22, thats a last resort. As far as repairs
go start with the most major one. Dont blindly recap or replace
tubes that check weak. Most old Zeniths come to life & work
fine with questionable parts. Its just the way they are.
Best is to post a pix showing the symptom. True content from a
VCR or DVD are best. Test patterns can also help sometimes.

73 Zeno:smoke:
LFOD !

I received my RF modulator today. I powered up the Zenith with the modulator attached to a VCR, DVD player, DVR. The picture looked the best using the DVR. You were spot on correct. The old Zenith doesn't work half bad just the way it sits. The picture on all sources is still a little fuzzy around the edges. The picture seems a tad out of focus, not quite straight on the screen.

But, watching one of the channels that play the old black and white re runs nets a very decent picture. This old tube gear still amazes me. The Zenith was used for countless hours when I was kid, still works.

Thanks for the advice!

dieseljeep
08-04-2019, 10:07 AM
So, last night I powered up the old Zenith over a couple of hours using a variac. The old girl did fine, screen is bright, no issues. I took the set in the house and realized that I don't have one device that I can use to drive the audio or video. I ordered a RCA compact modulator from Amazon that I think will allow me to use the rca out from my dvr, into a coax that hooks to an adapter, then attaches to the screw input terminals on the back of the set. Will report back when the device arrives.

Isn't there any Charity or thrift shops around your area? I've bought countless modulators, DTV convertors, coax connectors and other items, all for a fraction of new. My favorite haunt is one in an area where there is a lot of older folk moving out of state or moving into smaller quarters, so there's a good selection.
BTW, those Small Zenith sets were great for resale, they stayed sold. :thmbsp:

Tube TV
08-04-2019, 10:42 AM
That's a pretty decent picture!
As for picture being straight, you only need to adjust the yoke.
There should be a band type clamp on the back of the yoke on the neck of the crt.
Loosen the screw and turn the yoke slightly till the picture is straight.
Also check that the yoke is in toward the bell of the crt as far as it will go.
It's very likely that it's shifted back and to its side a bit over time or if it was jarred at some point. If the yoke is back that will cause there to be less focus especially on the outer edges.

Jeffhs
08-04-2019, 11:05 AM
I received my RF modulator today. I powered up the Zenith with the modulator attached to a VCR, DVD player, DVR. The picture looked the best using the DVR. You were spot on correct. The old Zenith doesn't work half bad just the way it sits. The picture on all sources is still a little fuzzy around the edges. The picture seems a tad out of focus, not quite straight on the screen.

But, watching one of the channels that play the old black and white re runs nets a very decent picture. This old tube gear still amazes me. The Zenith was used for countless hours when I was kid, still works.

Thanks for the advice!

I agree. Your set does make an excellent picture on your area's satellite TV service; this was a hallmark of Zenith television (and Zenith electronics in general) from the company's beginnings until its untimely ending in the late '80s.

You say, however, that you are "lost in the desert" between Phoenix and Tucson. Does your area not have cable service? I wonder about this because these days, most areas have some kind of cable service, except very small towns or rural areas hundreds of miles away from any major city. I realize where you are (or anywhere else, because all TV is digital these days) you won't get anything on a standard TV antenna, but I would guess your satellite does receive broadcast TV from either or both Phoenix and Tucson, in addition to most cable networks such as CNN, MTV, MSNBC, FOX/FOX News, et al.

Zenith electronics (not just TV sets) were made to last, and were quality equipment from the beginning (the company was founded in Chicago in 1918) until the Zenith Radio Corporation was taken over by Korean electronics giant LG in the late 1980s-early nineties.

I've owned Zenith TVs and other gear for years and was very disappointed, to say the least, when they left Chicago. From about 1982 until 1999 I had a four-mode stereo system which had been built to Zenith's standards, but had been manufactured in Korea. The unit was still one of Zenith's best in the '80s. I also owned two 13" Zenith portable color TVs, one made in 1979, the other in '83; both sets had excellent pictures.

Unfortunately, these sets were lost when I moved in late 1999. I did, however, manage to keep my Zenith SMS1917SG 19" color table model set. The last time I used it, with an RF modulator and a Roku streaming video device, the Zenith 19" set still worked as well as it always did at my former home, and still does to this day. Even though I don't use it much (except to test it every few months or so) since getting a flat screen in 2010, I am going to hold on to this set as long as it works since, as the expression goes, they don't make them (Zenith TVs) like that anymore.

dsndblm
08-04-2019, 11:02 PM
Isn't there any Charity or thrift shops around your area? I've bought countless modulators, DTV convertors, coax connectors and other items, all for a fraction of new. My favorite haunt is one in an area where there is a lot of older folk moving out of state or moving into smaller quarters, so there's a good selection.
BTW, those Small Zenith sets were great for resale, they stayed sold. :thmbsp:

We do have a Good Will and Salvation Army. But, I've never seen much of anything in the way of electronics in either. I work in Tempe, Az. Same story in the Goodwills there. Most of this part of the state is too new for much old electronics. The modulator was under $20 shipped through Amazon.

dsndblm
08-04-2019, 11:03 PM
That's a pretty decent picture!
As for picture being straight, you only need to adjust the yoke.
There should be a band type clamp on the back of the yoke on the neck of the crt.
Loosen the screw and turn the yoke slightly till the picture is straight.
Also check that the yoke is in toward the bell of the crt as far as it will go.
It's very likely that it's shifted back and to its side a bit over time or if it was jarred at some point. If the yoke is back that will cause there to be less focus especially on the outer edges.

I'll check the CRT as soon as possible. Thanks for the advice. That would be an easy fix.

dsndblm
08-04-2019, 11:13 PM
I agree. Your set does make an excellent picture on your area's satellite TV service; this was a hallmark of Zenith television (and Zenith electronics in general) from the company's beginnings until its untimely ending in the late '80s.

You say, however, that you are "lost in the desert" between Phoenix and Tucson. Does your area not have cable service? I wonder about this because these days, most areas have some kind of cable service, except very small towns or rural areas hundreds of miles away from any major city. I realize where you are (or anywhere else, because all TV is digital these days) you won't get anything on a standard TV antenna, but I would guess your satellite does receive broadcast TV from either or both Phoenix and Tucson, in addition to most cable networks such as CNN, MTV, MSNBC, FOX/FOX News, et al.

Zenith electronics (not just TV sets) were made to last, and were quality equipment from the beginning (the company was founded in Chicago in 1918) until the Zenith Radio Corporation was taken over by Korean electronics giant LG in the late 1980s-early nineties.

I've owned Zenith TVs and other gear for years and was very disappointed, to say the least, when they left Chicago. From about 1982 until 1999 I had a four-mode stereo system which had been built to Zenith's standards, but had been manufactured in Korea. The unit was still one of Zenith's best in the '80s. I also owned two 13" Zenith portable color TVs, one made in 1979, the other in '83; both sets had excellent pictures.

Unfortunately, these sets were lost when I moved in late 1999. I did, however, manage to keep my Zenith SMS1917SG 19" color table model set. The last time I used it, with an RF modulator and a Roku streaming video device, the Zenith 19" set still worked as well as it always did at my former home, and still does to this day. Even though I don't use it much (except to test it every few months or so) since getting a flat screen in 2010, I am going to hold on to this set as long as it works since, as the expression goes, they don't make them (Zenith TVs) like that anymore.

We are located about 40 miles south east of Phoenix. Not quite as desolate as I made it sound. We get clear radio signals from Phoenix and Tucson. When analog TV was around, we were able to pick up stations from both cities.Although, thinking about it, since I made this Videokarma account, my town has tripled in size, Phoenix has added about 3 million people. This state is growing quick, too quick.

I agree with you on Zenith quality. I had two Transoceanic radios that I restored and eventually sold. They were built well! I bet my little TV has easily a couple of thousand hours of use. It played all day when I was a kid.

I might buy a digital antenna, I have a digital to analog converter that I bought at a hamfest a few years ago. Could be a good combo for the Zenith.

dieseljeep
08-05-2019, 09:34 AM
We are located about 40 miles south east of Phoenix. Not quite as desolate as I made it sound. We get clear radio signals from Phoenix and Tucson. When analog TV was around, we were able to pick up stations from both cities.Although, thinking about it, since I made this Videokarma account, my town has tripled in size, Phoenix has added about 3 million people. This state is growing quick, too quick.

I agree with you on Zenith quality. I had two Transoceanic radios that I restored and eventually sold. They were built well! I bet my little TV has easily a couple of thousand hours of use. It played all day when I was a kid.

I might buy a digital antenna, I have a digital to analog converter that I bought at a hamfest a few years ago. Could be a good combo for the Zenith.
You have to get a Zenith DTV convertor. Keep your Zenith all Zenith. :D

old_coot88
08-05-2019, 11:47 AM
My Zenith DTV box was virtually bulletproof until it aged about 10 years, then started going wonky. But turned out to be an easy fix. Discussion here -

http://www.videokarma.org/showthread.php?t=271242&highlight=old_coot88

Works like brand new again.

Electronic M
08-05-2019, 12:10 PM
Technically you probably didn't need to buy a RF modulator if you already owned a VCR. About 95% of VCRs have a built in RF modulator. The TV/VCR button on the remote (also sometimes on the front of the VCR) will turn the modulator on and off. Also popping a tape in and letting it auto play usually activates the modulator too. You can even pass an external audio/video source through the VCRs modulator by activating the modulator, connecting the device to the VCRs AV input, and tuning the VCRs tuner below channel 2 to select the input be tuned.

Back when there was analog cable you could also use the VCR to convert cable channels 14 and up (which are different frequencies than 14-83 UHF broadcast) to channel 3/4 for viewing on a vintage TV.

dsndblm
08-05-2019, 04:25 PM
That's good to know. Thanks!


QUOTE=Electronic M;3213393]Technically you probably didn't need to buy a RF modulator if you already owned a VCR. About 95% of VCRs have a built in RF modulator. The TV/VCR button on the remote (also sometimes on the front of the VCR) will turn the modulator on and off. Also popping a tape in and letting it auto play usually activates the modulator too. You can even pass an external audio/video source through the VCRs modulator by activating the modulator, connecting the device to the VCRs AV input, and tuning the VCRs tuner below channel 2 to select the input be tuned.

Back when there was analog cable you could also use the VCR to convert cable channels 14 and up (which are different frequencies than 14-83 UHF broadcast) to channel 3/4 for viewing on a vintage TV.[/QUOTE]

Popester
08-05-2019, 04:52 PM
Regarding post #11, I'm not even sure you need to check the CRT at all. Just looking at the pictures you posted of the jug I would say it's in good shape. No silvery appearance to me. They have that silvery look to them with little brightness available when they weaken. But I understand if you want to establish a baseline to see where it checks on the dials of a CRT checker.