1972 Zenith model T-2657 19" B&W TV set

[electra225]

I have had this set for close to 40 years. A friend dug it out of the dumpster and brought it to me, somewhere around 1984. I don't remember the last time I've had it on, and can't remember if I watched it at all. It has just kind of "hung around" too good to toss, not enough interest to do anything with it. While I'm waiting for the decal for my little record player project, I got the brilliant idea to tinker around with my B&K 1077B TV Analyzer. I needed a TV to analyze, and this Zenith was the closest at hand. This set is in nice, if a tad dirty, condition. The only cosmetic fault I see is a broken/missing knob for the vertical hold control. I have a set of knobs that will work. I decided to put the set on the bench and do a "Shango" analysis on it. I don't have a meter to check cathode current on the horizontal output tube like he always likes to do, so I had to improvise a bit. This is a hot chassis Zenith. The tubes are coded from the 8th to the 13th week of 1972. Most, if not all, of the tubes in the vertical circuit have been replaced, as have the 6GH8A horizontal oscillator tube and the 21HB5 horizontal output tube. The high voltage rectifier is still original, as are all the tubes in the tuner and in the IF strip. The 8BA11 tube is original, I believe it to be the sound detector/ audio output tube. The chassis had some dust, but it sure wasn't nasty by any stretch of the imagination. I took a brush and the shop vac and cleaned and dusted well. I removed each tube, ran them thru the tester and cleaned those. I removed the horizontal output tube then used a jumper wire across pins 1&12, the filament pins, so I could power up the chassis with no HOT in the circuit. This set is new enough, there are no paper caps under the chassis. And, in fairness, it probably would have worked just plugging it in and turning it on. I powered up with the KAW and Variac/dim bulb setup. I started at 75 volts, mindful that the 20 volts or so the HOT would consume was added to the heater string. So as not to over-voltage the "picture bulb", I kept the line voltage under 100 volts. I had checked the "jug" and found it to test almost like new. This does not appear to be a high-hour set, judging by the amount of "fuzz" that had accumulated in the high voltage components. Everything ran cool, the wattage listed for the set is 190 watts. Without the high voltage in play, it pulled about 65 watts. I got audio hash even though the picture tube was dark. I let it run this way for about 30 minutes, in an attempt to reform the electrolytic filter capacitors, another process Shango likes to do. I'm not sure I believe in that, but it doesn't hurt anything to try. I then powered down and "re-populated' the HOT, horizontal output tube. I started at about 100 volts so the horizontal oscillator would run. I could hear the vertical and the horizontal running, but the picture tube remained dark. I looked on the cabinet, located the brightness control and found that the reason I had a dark tube. I finally got a dim picture, covering about 3/4 of the screen. I cranked the voltage up to 120 and found I had a nice full screen. There was a lot of flashing in the screen, caused by dirty tube pins on the 10GN8 vertical oscillator tube, a dirty tuner, and dirty controls. It does appear that the vertical and the horizontal are stable at this point. I never did connect the TV Analyzer, which is my next step. This will confirm that the sync is stable and will let me know what adjustments I need to make. I've never used the Analyzer, so this is all new to me. I want to get this set sorted, then start using it to watch antenna TV. You TV guys are more than welcome to jump in here and bail me out. I haven't gotten zapped yet, and I'll admit I'm not very brave around high voltage. I have some pictures to share as soon as I get them loaded. It pulls 158 watts with the high voltage up and running.

[TC Chris]

Photo?

Chris Campbell

[William]

Yes, photo please!

Bill

[electra225]

Patience, patience.....

Okay, here they are. You will notice in the last picture the big goose egg in the image. You will also notice the image does not fill the screen vertically. You will also notice the TV has a full raster. Hence, may we conclude that my Analyzer needs analyzed? Probably has some wonky caps and or a couple weak tubes in the video circuits.

The tubes in this TV were made by Sylvaia, GE and RCA. There are three 4BZ6 tubes in the IF strip. One made by GE, one by Sylvania, one by RCA. The picture bulb was made by Sylvania. I cleaned the tuner (my first time doing that) and all the controls. The vertical is rock solid until the Analyzer messes it up. The Analyzer is an amazing piece of test equipment. I'm thrilled to have it. It will save me a lot of time. If I was a real "TV guy" and wanted a whole shop full of TV test equipment, the Analyzer might be a shortcut instrument. For someone like me who is only into TV because he has some and doesn't want to toss them, it's a life saver.

[William]

It looks like you might have a good set there, Greg. This is the first TV that I have seen that the Flyback components are not enclosed in a metal box. Zeniths of that era were definitely well built.

Bill

[electra225]

As you know, Bill, I avoid Zenith radios like the plague. But I am impressed with a Zenith TV. Those little posts around the tubes let you measure voltages and run testing without having to pull the chassis to make measurements under the chassis. I really like that. This thing is 50 years old, and, minus a couple adjustments it needs, still works perfectly. That is impressive.

Without inappropriately melding topics, I connected the Analyzer to a later RCA color set that I know to be in good operating condition. I still got the "pregnant" image like I did on the Zenith. I will retain other comments for a topic on the Analyzer. The TV is mostly okay, it's the Analyzer that needs attention.......

[TC Chris]

As you know, Bill, I avoid Zenith radios like the plague. But I am impressed with a Zenith TV. Those little posts around the tubes let you measure voltages and run testing without having to pull the chassis to make measurements under the chassis. I really like that. This thing is 50 years old, and, minus a couple adjustments it needs, still works perfectly. That is impressive.

The little towers were also solder posts for a non-PC chassis, right?

Chris Campbell

[electra225]

I think Zenith called those little posts a "Service Saver" chassis. They appear to be a part of the tube socket assembly. My understanding is the posts that hold those assemblies into the chassis are points where you can connect test equipment to common negative. Maybe some of the TV gurus on here can clarify that point.

[hermitcrab]

Is it strictly a tube set or a hybrid?

[electra225]

Elton, I believe it to be an all-tube set. The UHF tuner is solid state, of course. It has 14 tubes, including the picture tube. I'd call it a late tube, Compactron set. Zenith put their transistors in obvious places, and I don't see any. In fairness, I don't have the drawing for this set, so there is that. The horizonatal oscillallator is a 6GH8A, but the horizontal output tube is Compactron, as is the audio detector/audio output tube. The sync tube is Compactron. The IF strip has three 4BZ6's, the vertical oscillator and the vertical output tubes are not Compactron. It's a pretty simple TV, beautifully built. If you look at the second picture, just to the right of the left chassis support upright, that is the wire for the power to the switch. The interlock is below the white plug on the chassis. And to the rear of that white plug, there is a stake. That stake/lug is common negative. You can do almost all voltage tests from the top of the chassis using that stake for common negative. How much easier to service could they have made it? I think even I could actually fix this set if it came to that. I can see why the TV guys have a lot of respect for Zenith TV sets.

[TC Chris]

I can see why the TV guys have a lot of respect for Zenith TV sets.

The guy who got me into ham radio, Mr. McKenzie, operated a TV service shop and also sold Zeniths. "Universal TV"

Chris Campbell

[William]

Universal TV and Electronics was also located in the next town south of me and is where every member of my family purchased their electronics. I'm friends with the current owner, but he just retired, at 70 and just plain got tired of dealing with the public. No one in the family wanted to take over the business which is very sad. I happy Mike was able to retire, but I sure wish someone would have come up to the plate and continued on.

Bill

[electra225]

Starting when I was 13, I worked three hours on Saturday mornings for Mr. Wells, the local Zenith dealer. He had a contract with a furniture company that sold Magnavox but did not have their own service department. Mr. Wells would only work on Zenith. NOTHING else. My job was to get to his basement shop at 5 am on Saturday mornings, then get TV sets ready to do alignments on when the test pattern came on Channel 10 at 6 am. He would put the TV's under test on a long bench on one wall of the shop. There was a mirror the full length of the bench. He would watch the TV screen in the mirror and do his alignment procedures from the back. My job was to make sure they were working correctly, no rolling, good audio and no smoke, all ready to go at 6 am. The test pattern was only on until 7 when the TV station came on. Now you can put the test pattern on your phone, or on your TV Analyst...

Mr. Wells only used genuine Zenith test equipment, or aftermarket equipment specifically recommended by Zenith. He drove a Ford Country Squire wagon, the model with wood trim on the side. He had a Zenith sign on both front doors. The last one he had when I worked for him was a '68 model with hidden headlamps and a 390.

[Hi-Fi-Mogul]

That is such a cool story, Greg.

Mr. Wells was a down to earth, creative guy.
The mirror idea is simply of those years.

Yes, I remember when I was a tot, when the
TV broadcast would go Off-Air around maybe
mid-night, and the test pattern came on.

Later years, you just got TV "white noise", no
cool test pattern.

[electra225]

The mirror Mr. Wells used in his basement TV shop had an interesting story itself. There was a bar/restuaurant/gin joint/bawdy house during Prohibition they called the "Flying T". The building once housed a large funeral home and was built in the late 1800's. During Prohibition, one could buy an illegal adult beverage, engage in an illegal gambling enterprise, or could buy the affections of a lady of the evening. It naturally developed a racy reputation and was the subject of ladies' puritan groups. There was a fire in the building in the late 1930's, so the building sat in disrepair and boarded up until sometime in the early 1950's. The owner of the establishment had passed since the fire, so the family donated the property to the local American Legion chapter to tear down the old structure to accomodate their new building. The bar from the speakeasy was 32' long, make of solid mahogany. A local artisan took on the task of removing the bar and restoring it to be used in the new American Legion. The mirror behind the bar was over 8' tall and 32' wide, being made up of 4' x 4' sections of leaded glass. The American Legion took 16' of the mirror and Mr. Wells took the other 16'. It went from floor to ceiling on one wall in the basement of Mr. Wells' home where he had his TV repair shop. Mr. Wells made the bench so you could put portable sets and small consoles on the bench, with room to slide heavy consoles and Stereo Theater-type instruments under the bench. There were double outlets on each upright holding up the bench and an antenna wire hanging down from the ceiling. He used those clothes pin type connectors on the TV antenna wires so they would be easy on and off. Mr. Wells was an elder in the church, and took a lot of ribbing for his whorehouse mirror. "The only church elder with a whorehouse mirror in his house". Mr. Wells was not given to participating in grab-ass, but took the ribbing in good humor. That old mirror made him a lot of money.

[electra225]

I sure wish I had Mr. Wells around again. I'm not sure the picture on this TV is as good now as it was that I posted above. I had some problems with the contraption I used to adapt the antenna connections on the TV to the Analyzer cables. The picture is washed out, with poor contrast and poor focus. I don't think the problem is in the Analyzer because I can increase the settings on the video control and RF attenuator until it overloads the front end of the TV. The contrast control really doesn't do much. I had a shop lamp on next to the TV and turning that off helped some, but the pictures still looks washed out to me. My next step is to fix the antenna adapter and get a VCR connected to it. The tuner doesn't seem to be dirty anymore. None of the controls that I used were scratchy. I have a beautiful raster, rock solid vertical and horizontal lock. Good audio, not even any Zenith buzz.

[electra225]

I may be worrying about something that is somewhat normal.

First, let me say how much respect I have for anyone who seriously works with these old TV sets. They have LOTS more patience than I do. Tinker. You gotta twiddle and tinker to convince one of these old sets to work. I had the contrast up WAAAAYY over yonder too high. I backed off on the AGC just a tad. I think there is a focus control, but you have to remove the back to get to it. The image is for sure out of focus. I found an old Ronald Reagan black and white DVD and connected the device to the TV. I found a better antenna doodad, which helped considerably. The pictures is better, but I still believe it's washed out. I REMEMBER it being more sharp and detailed. The black is too gray. Or am I expecting something it never had? I may run it awhile before I tinker much more. Video linearity and height seem okay. Maybe I need to run it awhile to wake up the picture tube?

[electra225]

I fired up this old set this afternoon. I played a couple Andy Griffith DVD's and then "The Sante Fe Trail" with Ronald Reagan and Olivia De Havilland. I let it run for about an hour before I did any twiddling with controls. The longer it ran, the better the picture got. It now has a very respectable picture, no buzz, but the focus could certainly be better. The picture is not so washed out as it was. I set the AGC control right on the edge of distortion, then cut back on the contrast control, darkened the screen a bit. I may need to get a print on this chassis to clear up a couple questions I still have. There has to be a focus control someplace. The vertical height is good, horizontal seems good, the picture is rock stable. All in all, if something doesn't fry being on so long after so long a rest, I'd say it represents the brand Zenith well. I have essentially done nothing to this thing except some cleaning and some adjusting. The controls all seem good. I fixed my broken DVD player and used it all afternoon and it's still running. Next up is to figure out why the VCR part eats tapes. It plays them okay, but good luck getting them back. I don't know whether something is jamming, of if the belt starts slipping just when the tape starts lifting on its way out. It may have been 30 years since I had used this TV very much. My plan is to rig it up to receive OTA TV. I have no idea how that will work. IF I get that figured out, my next plan is to find an agile modulator and see what I can do with it.

[electra225]

I realize everybody knows this but me, but.....

Before you use any medium to test the performance of a TV you are working with, first test that medium on a set known to be good. In other words, play any DVD you use for test on the flat panel set in the house to make sure you are not watching a wonky movie then trying to "fix" the TV to compensate. Don't ask......

[William]

Your screens shots look pretty good, Greg.

Bill