View Full Version : 1967 Zenith table set with 25NC37 Chassis


captainmoody
09-30-2015, 10:45 AM
I picked up this one from an Estate a few months ago. I also priced/sold many other items for the lady.

The owner sadly ended his life in 1985, and his Wife left everything sitting untouched where it was last used.

The Zenith was still on the bench, the test equipment still sitting on the shelf above, many nos tubes and bins of caps, resistors, fasteners, on another shelf on the wall.

He at some time took an Electronics course through the mail, and many items (as well as a neat b/w TV) were Conar brand.

This set still works, needed a little help with a 'lytic, but still produces a great picture!

I don't think I have ever run across this model in the wild.. All the ones I ever worked on were the later, smaller, metal cabinet sets.

The Chassis is an neat, smaller package, but still uses the 6BK4 HV Reg.

drh4683
09-30-2015, 12:13 PM
Nice catch! You've indeed found one of the scarcest of the scarce. I've never spotted one before either. I believe that was Zenith's very first small screen table color set. Even though it's a '66 chassis number, I think they were introduced as '67 models. Nice to see rare sets like this are being found and saved!

captainmoody
09-30-2015, 12:31 PM
I remember you telling me about the unique chassis, with the shunt reg.

Wonder how many they made?

It still makes me sad the poor guy did himself in. From the looks of his shop , he knew what he was doing as a Tech. All his kits he built were soldered perfectly, every wire in place. All the tube stock had NEW tubes in the boxes, no "used but may be good" crap. Everything was arranged orderly, all his stock was Sprague, or RCA/Zenith.. No cheap junk.

Olorin67
09-30-2015, 01:13 PM
nice find! cant be many of those around.

dieseljeep
09-30-2015, 01:30 PM
nice find! cant be many of those around.

I had one customer that had one. Never needed much work.
IIRC, it's similar to my "N" roundie.
The rectangular set, both the 19" and 23", came out in late 1965, but in a limited supply. The set used a 6C4 PC corrector.
The weight went in before the name went on! :yes:

jstout66
09-30-2015, 01:42 PM
That's a nice one. I didn't think I'd ever see one again. We had ONE on our service route. IIRC, it weighs a TON.
If you ever decide to sell it Dwight, let me know. I don't have really old Zenith stuff anymore.

Olorin67
09-30-2015, 01:55 PM
Not a lot of the metal cabinet tabletops survived. I have a 23V metal cabinet set with remote. Mine might be a year or two newer...Still a bit buried in my storage locker.

zeno
09-30-2015, 05:24 PM
I remember those. Still in the '68 catologue. One
remote & 2 others. I dont think they sold well
cause you could get a 20" Zenith & its almost
the same footprint. Also looks more normal with
all nobs on the right.

73 Zeno:smoke:

drh4683
09-30-2015, 06:37 PM
The 25NC37 indeed uses the 6BK4 and a 6C4 pincushion correction. It also has a 19EYP22 crt. That's also a flipper chassis as they put the HOT and the HV reg in that PITA spot behind the HV cage. Very similar to the more common '67 20X1C38 chassis except the 20X1C38 combined the PC correction into 1/2 of a 6KT8 which also serves as the color amp and the 6BK4 gets replaced by the 6HS5 pulse regulator. Same chassis footprint and general tube layout though.

Never did discover any documents with production figures for Zenith. I've had better luck acquiring leftovers from Motorola employees than I ever did with Zenith.

Olorin67
09-30-2015, 06:49 PM
Anyone know where to find Zenith sales catalogs of the 60's? Are they online anywhere? I have a few I'd love to identify and figure out where they stand in the model lineup.

Electronic M
10-01-2015, 12:46 AM
Wow, I did a double take when I saw the color knob in that pic.....I thought it was a monochrome set until I enlarged it. I'd love to own one of those some day.

dieseljeep
10-01-2015, 09:48 AM
The 25NC37 indeed uses the 6BK4 and a 6C4 pincushion correction. It also has a 19EYP22 crt. That's also a flipper chassis as they put the HOT and the HV reg in that PITA spot behind the HV cage. Very similar to the more common '67 20X1C38 chassis except the 20X1C38 combined the PC correction into 1/2 of a 6KT8 which also serves as the color amp and the 6BK4 gets replaced by the 6HS5 pulse regulator. Same chassis footprint and general tube layout though.

Never did discover any documents with production figures for Zenith. I've had better luck acquiring leftovers from Motorola employees than I ever did with Zenith.

The "N" line chassis had the metal shield that had to be removed to gain access to the high voltage rectifier. Also, the 6BK4 and the 6JS6 had the be removed to open the door. Lazy, sloppy technicians? bent the h*ll out of everything, instead of removing the shields.
The "N" chassis, 23V set had some kind of a crude looking adjustment device on the CRT neck, made of Masonite. Don't remember what it did. I was the only 23V Zenith that used it. :scratch2:

captainmoody
10-01-2015, 09:56 AM
Doug has the answer to that.. I forgot what he said it was..

Oh, Dieseljeep.. I know what you are talking about. One of my techs used to BREAK off the tabs that held in the 9-160 modules, and throw away the red lock down. Ugh.. I hated that, and put an end to that crap as soon as I found out..

andy
10-01-2015, 10:42 AM
...

drh4683
10-01-2015, 10:43 AM
The "N" chassis, 23V set had some kind of a crude looking adjustment device on the CRT neck, made of Masonite. Don't remember what it did. I was the only 23V Zenith that used it. :scratch2:

Ah, yes! Those were the big post-deflection purity rings! Zenith did it that way on the M and N line 23" sets. Very large and bulky apparatus and was secured with heavy copper braided cables that curved around the bell of the CRT. An unusual approach to purity adjustment. Not sure why Zenith did it that way in the beginning as I think the rest of the industry was using the much smaller and simpler purity ring assembly at the end of the tube.

BigDavesTV
10-01-2015, 11:34 AM
Nice looking and uncommon Zenith! Looking forward to "Simulated Television Reception" pictures!:) Remember when the pictured ads used to say that in fine print, below the picture of the TV for sale!

Electronic M
10-01-2015, 07:49 PM
Ah, yes! Those were the big post-deflection purity rings! Zenith did it that way on the M and N line 23" sets. Very large and bulky apparatus and was secured with heavy copper braided cables that curved around the bell of the CRT. An unusual approach to purity adjustment. Not sure why Zenith did it that way in the beginning as I think the rest of the industry was using the much smaller and simpler purity ring assembly at the end of the tube.

Perhaps they did that (assuming it was adjusted electrically) to try to put the purity adjustments on the front....Zenith seemed to like to make as many of the service adjustments front-adjustable as possible.

dieseljeep
10-01-2015, 08:05 PM
Ah, yes! Those were the big post-deflection purity rings! Zenith did it that way on the M and N line 23" sets. Very large and bulky apparatus and was secured with heavy copper braided cables that curved around the bell of the CRT. An unusual approach to purity adjustment. Not sure why Zenith did it that way in the beginning as I think the rest of the industry was using the much smaller and simpler purity ring assembly at the end of the tube.

I thought it was for purity adjustment.
I didn't know, that there was an "M" chassis 23V rectangular set, just the "N" models.
I know, that RCA had a CTC17E chassis, that was their first 23V set. It had the same control panel as the CTC16E roundie. Most of them, didn't have that great of a picture and had purity problems. :scratch2:

dieseljeep
10-01-2015, 08:11 PM
Perhaps they did that (assuming it was adjusted electrically) to try to put the purity adjustments on the front....Zenith seemed to like to make as many of the service adjustments front-adjustable as possible.

It was rear adjustable, with two large tabs, to move around.
If anyone remembers the Motorola ETS908 chassis, it had a dynamic blue lateral magnet, that was adjusted from the front, on the convergence board.
In the early days, they all had their quirks. :scratch2: