1950s or '60s vintage Zenith TVs, Need some info

[vortalexfan]

Originally Posted by Electronic M

Got HV? Got correct CRT grid-cathode voltage? Are the fuses all good?

Tubes being good doesn't mean squat if there's significant issues in other components. And something tiny and easy to change can prevent raster from existing.

No, there doesn't seem to be HV which is kind of confusing because the HV rectifier is in really good shape and the Flyback is in really shape (no melted wax etc.)

The picture tube is glowing in the back and the Picture tube looks to be low hours as the cathode material inside is a shiny silvery color yet and not a dark gray color like a high hours tube would be.

I could pull the chassis and check some of the components underneath but in all honesty except for a bunch of dirt inside the chassis (its literally dirt, not dust, like it may of been in a garage or barn for many years) the set seems to be a low hour set.

from what I could see of the underside of the chassis from the topside I did see one Bumblebee cap (no idea of the value on it though as I couldn't make out the color code on it.)

As for the Bugeye TV I replaced all of the Deflection tubes on the TV and tried to temporarily hook up an 8 ohm bookshelf speaker to the output transformer, and turned on the TV and all I got out of the TV was a loud hum from the speaker which at first I thought maybe it was related to bad filter caps but then when I turned down the volume the hum went away.

Is it possible for an impedance mismatch in a tube audio circuit to cause a hum that can be adjusted by the volume control?

EDIT: Definitely failed filter caps, and I checked the date code on the picture tube on this TV and it does seem to be the original picture tube (or else a NOS tube because the picture tube is a GE branded Picture tube with a Date Code of 58-17 or 17th Week of 1958 which is right around the time period this TV was made, also I think the Selenium Rectifiers are going bad because when I powered on the TV I smelled a burning surfury smell coming from the TV that seemed to be coming from the Selenium Rectifiers.

So how do you remove the chassis out of the Zenith Bugeye TV? I'm asking because I don't see any obvious ways to get the Chassis out (marked screws or anything), also when I was trying to take the socket off the back of the CRT on the Zenith Bugeye TV I accidentally pulled the picture tube's base off (the plastic part with the pins on it that the socket plugs into) thankfully the wires are still intact but trying to feed the wires back into the pins in the base for resoldering is going to be tricky, also trying to figure out how to reglue the base back onto the CRT so it doesn't break off again.

[vortalexfan]

OK, so I downloaded the Sam's Photofact for the big Zenith, which is a 15L22U Chassis, and according to the Sam's my TV was supposed to be Remote Controled Model (they don't give any other arrangements of that particular chassis) and the fact that my TV clearly has a spot in it for a remote control receiver sub-chassis, but there's nothing there clearly shows that more than likely this was indeed a remote controlled model originally but then possibly the original owners of the TV were having issues with the remote control functions so they decided to have the repairman remove the remote control receiver subchassis from the TV so they didn't have to worry about it anymore so then they just operated it "manually" (using the push-button in the front of the TV) and just called it good enough.

Also according to the Sam's that auto/ manual switch on the back of the TV was indeed a remote control receiver defeat switch just like I said it was, and the fact that the hole was actually punched out on the back cover of my TV rather than just being a "blank" (unpunched) hole is another reason why I suspect this TV originally was a remote controlled set.

[dieseljeep]

Originally Posted by vortalexfan

OK, so I downloaded the Sam's Photofact for the big Zenith, which is a 15L22U Chassis, and according to the Sam's my TV was supposed to be Remote Controled Model (they don't give any other arrangements of that particular chassis) and the fact that my TV clearly has a spot in it for a remote control receiver sub-chassis, but there's nothing there clearly shows that more than likely this was indeed a remote controlled model originally but then possibly the original owners of the TV were having issues with the remote control functions so they decided to have the repairman remove the remote control receiver subchassis from the TV so they didn't have to worry about it anymore so then they just operated it "manually" (using the push-button in the front of the TV) and just called it good enough.

Also according to the Sam's that auto/ manual switch on the back of the TV was indeed a remote control receiver defeat switch just like I said it was, and the fact that the hole was actually punched out on the back cover of my TV rather than just being a "blank" (unpunched) hole is another reason why I suspect this TV originally was a remote controlled set.

AFAIK, the remote unit has to be in there to operate the motor driven tuner.
I has relays and other parts for the motor drive. The metal cabinet sets generally used the same back for all the models of the same size. It's more cost effective.

[vortalexfan]

Originally Posted by dieseljeep

AFAIK, the remote unit has to be in there to operate the motor driven tuner.
I has relays and other parts for the motor drive. The metal cabinet sets generally used the same back for all the models of the same size. It's more cost effective.

Hmm, I'm surprised, because RCA and Philco for their remote control TVs (and non-remote control sets) used different backs for example I had a 19" Philco Townhouse TV from 1962 (same time period as this TV) and they were available as remote control and non-remote control models, and the non-remote control models had the remote control defeat switch cutouts molded into the back cover but they weren't cutout (plastic rear covers) same goes for my 17" RCA TV (also from abt. 1962) which also came with or without the option for a remote, and the back cover on my RCA has the remote control defeat switch hole molded into the back cover but its not cut out the units that originally came with a remote had the hole cutout for it, and the units that didn't didn't have the hole cutout for it. Now of course that might be the difference between a plastic cover vs. a metal cover but that still shouldn't make a difference I wouldn't think.

Anyways Why would a remote control model vs. a non-remote model make a difference in whether or not the front push-button would work or not, in a motorized tuner set? Shouldn't the Motorized tuning still work on these TVs even if the remote was out of the picture on a remote controlled unit?

[Electronic M]

I have seen factory non-remote power tuning Zenith's a few times before and they do work without the remote chassis. Based on what I have seen of the SC600 combo set I own I believe the tuner motor can operate without the remote chassis (as long as you connect it to a source of 120VAC). I'm planning to try it out soon without the SC chassis to test the motor.

You may want to decide the letter suffixes on the model number. My 1959 Zenith wasn't optioned with a remote, but the cabinet and chassis had provisions for one such that I could add one easily.
IIRC in 59 they had a U model suffix for the cabinet and an R suffix for remote. (There would also have been a suffix for non-remote power tuning). Note I may not be remembering the exact letter used to designate the option.
Basically the model number for example cabinet with base options of manual VHF only tuning would be something like B2506 (B being the year) and if you liked the cabinet but wanted it with UHF and remote you would order a model B2506UR. Some TV only sets also offered "HI-FI sound" which was a set of tone controls...IIRC those also had a suffix.

[damen]

If the set was remote the chassis number would end with the letter "Q".

[damen]

Do you see an opening in the front of the cabinet where the microphone for the remote had been ?

[vortalexfan]

Originally Posted by Electronic M

I have seen factory non-remote power tuning Zenith's a few times before and they do work without the remote chassis. Based on what I have seen of the SC600 combo set I own I believe the tuner motor can operate without the remote chassis (as long as you connect it to a source of 120VAC). I'm planning to try it out soon without the SC chassis to test the motor.

You may want to decide the letter suffixes on the model number. My 1959 Zenith wasn't optioned with a remote, but the cabinet and chassis had provisions for one such that I could add one easily.
IIRC in 59 they had a U model suffix for the cabinet and an R suffix for remote. (There would also have been a suffix for non-remote power tuning). Note I may not be remembering the exact letter used to designate the option.
Basically the model number for example cabinet with base options of manual VHF only tuning would be something like B2506 (B being the year) and if you liked the cabinet but wanted it with UHF and remote you would order a model B2506UR. Some TV only sets also offered "HI-FI sound" which was a set of tone controls...IIRC those also had a suffix.

OK, that makes more sense explained that way, I'm familiar with Zenith products but mostly their tube radios and record players, and their later Solid State TVs and their VCRs (which were rebadged JVC and Goldstar VCRs) but I'm not as familiar with their TVs from the 1950s and 1960s and how they worked and how they were or weren't equipped.

My bigger Zenith TV, the Model number is L2717U3 and the Chassis is 15L22 (at least according to the back cover).

So According to your explanation the "U" Suffix meant "UHF" so the what did the "3" Suffix after the "U" suffix refer to?

Also you said the the Letter Prefix at the beginning of the model number referred to the year the TV was made, so then what year does the letter "L" represent? Also My TV does have a tone control on the front of the cabinet in the "pencil box" compartment does that make it a "hi-fi" model or does it have to have both a bass and treble controls for that and not just a single tone control pot?

Also can the yoke still work properly without the plastic cover over it and without the centering ring?

I'm asking because the plastic cover that goes over the yoke on the big Zenith had more or less crumbled in several spots resulting in the centering ring falling off.

[vortalexfan]

Originally Posted by damen

Do you see an opening in the front of the cabinet where the microphone for the remote had been ?

I'm not sure, because wouldn't of the mic of been hidden behind the speaker grille?

[vortalexfan]

OK So I'm curious, the big Zenith TV of mine, has all of its original Zenith branded tubes in it and they are all sourced from different companies including Sylvania (Zenith's primary tube source), GE, RCA and several tubes in the IF and Audio section that were sourced oddly enough from Philips-Miniwatt in Holland, I say "oddly enough" for the Philips-Miniwatt sourced tubes in this set because I didn't think Zenith sourced OEM Parts such as tubes from Philips-Miniwatt during that time period in their history, and the reason why I know they are all original tubes and not replacements is because all of the tubes have matching date codes from between late 1963 to early 1964 which was about the time period we had thought this TV dated to possibly.

[Notimetolooz]

Originally Posted by vortalexfan

The picture tube is glowing in the back and the Picture tube looks to be low hours as the cathode material inside is a shiny silvery color yet and not a dark gray color like a high hours tube would be.


As for the Bugeye TV I replaced all of the Deflection tubes on the TV and tried to temporarily hook up an 8 ohm bookshelf speaker to the output transformer, and turned on the TV and all I got out of the TV was a loud hum from the speaker which at first I thought maybe it was related to bad filter caps but then when I turned down the volume the hum went away.

Is it possible for an impedance mismatch in a tube audio circuit to cause a hum that can be adjusted by the volume control?

EDIT: Definitely failed filter caps, and I checked the date code on the picture tube on this TV and it does seem to be the original picture tube (or else a NOS tube because the picture tube is a GE branded Picture tube with a Date Code of 58-17 or 17th Week of 1958 which is right around the time period this TV was made, also I think the Selenium Rectifiers are going bad because when I powered on the TV I smelled a burning surfury smell coming from the TV that seemed to be coming from the Selenium Rectifiers.

So how do you remove the chassis out of the Zenith Bugeye TV? I'm asking because I don't see any obvious ways to get the Chassis out (marked screws or anything), also when I was trying to take the socket off the back of the CRT on the Zenith Bugeye TV I accidentally pulled the picture tube's base off (the plastic part with the pins on it that the socket plugs into) thankfully the wires are still intact but trying to feed the wires back into the pins in the base for resoldering is going to be tricky, also trying to figure out how to reglue the base back onto the CRT so it doesn't break off again.

First off lets get your terminology correct, the silver coating in a tube is the "getter". It is a deposit of a metal that will grab any trace of oxygen in the tube. Sometimes it is silver, sometimes it is grey, it depends on how quickly it was deposited. When the getter starts to turn white it means there is too much gas in the tube for it to handle. The cathode is a very small cylindrical metal "can" shape with a small spot of white cathode material on the end. It is all but completely impossible to see from the outside.
An impedance mis-match would not cause hum.
Pulling the CRT base off is a rookie mistake. I'm sure you know how hard it is to find good CRTs today. Always hold the base with one hand and the socket in the other when separating the two. I think that at least one person on this forum has posted about re-connecting the base. I'm sure Phil Nelson of Phil's Old Radios had to repair one that was already loose. Generally you remove most of the old cement, clean the glass and base well, solder on extension wires to the one still on the tube, and remove all the solder inside the base pins. With the longer wires it is much easier to feed them into the socket. The original cement used a mixture of things like water glass, marble dust, shellac, etc. which is hard to find. Many people use "electronic safe" silicon sealant, (it does not smell like vinegar).
In fact Phil has a restoration article about a similar set.
https://www.antiqueradio.org/zen28.htm

[Electronic M]

Originally Posted by vortalexfan

OK, that makes more sense explained that way, I'm familiar with Zenith products but mostly their tube radios and record players, and their later Solid State TVs and their VCRs (which were rebadged JVC and Goldstar VCRs) but I'm not as familiar with their TVs from the 1950s and 1960s and how they worked and how they were or weren't equipped.

My bigger Zenith TV, the Model number is L2717U3 and the Chassis is 15L22 (at least according to the back cover).

So According to your explanation the "U" Suffix meant "UHF" so the what did the "3" Suffix after the "U" suffix refer to?

Also you said the the Letter Prefix at the beginning of the model number referred to the year the TV was made, so then what year does the letter "L" represent? Also My TV does have a tone control on the front of the cabinet in the "pencil box" compartment does that make it a "hi-fi" model or does it have to have both a bass and treble controls for that and not just a single tone control pot?

Also can the yoke still work properly without the plastic cover over it and without the centering ring?

I'm asking because the plastic cover that goes over the yoke on the big Zenith had more or less crumbled in several spots resulting in the centering ring falling off.

L would have been the 1964 model year introduced in late 1963 (like car model years are).

The option code leters I don't actually remember which letter goes with which option. My 1959 Zenith had notation on the tube chart that made it obvious what letter was used for UHF and what was used for remote sets, but it's been over a decade since I looked at it and that set is covered in a mountain of junk presently.

The High Fidelity sets always had bass and treble knobs, sets without that option often had a single tone control.

[vortalexfan]

Originally Posted by Notimetolooz

First off lets get your terminology correct, the silver coating in a tube is the "getter". It is a deposit of a metal that will grab any trace of oxygen in the tube. Sometimes it is silver, sometimes it is grey, it depends on how quickly it was deposited. When the getter starts to turn white it means there is too much gas in the tube for it to handle. The cathode is a very small cylindrical metal "can" shape with a small spot of white cathode material on the end. It is all but completely impossible to see from the outside.
An impedance mis-match would not cause hum.
Pulling the CRT base off is a rookie mistake. I'm sure you know how hard it is to find good CRTs today. Always hold the base with one hand and the socket in the other when separating the two. I think that at least one person on this forum has posted about re-connecting the base. I'm sure Phil Nelson of Phil's Old Radios had to repair one that was already loose. Generally you remove most of the old cement, clean the glass and base well, solder on extension wires to the one still on the tube, and remove all the solder inside the base pins. With the longer wires it is much easier to feed them into the socket. The original cement used a mixture of things like water glass, marble dust, shellac, etc. which is hard to find. Many people use "electronic safe" silicon sealant, (it does not smell like vinegar).
In fact Phil has a restoration article about a similar set.
https://www.antiqueradio.org/zen28.htm

Ok, I apologize for using the wrong terms for the parts inside the Picture tube, I was going by what I was loosely remembering Shango066 say about how he could tell if a picture tube was low or high hours which I guess I remembered the terms he used wrong.

As for the picture tube repair there's a lots of wire left so I should be able to fish the wire through (the wire leads didn't break off they just more or less slid cleanly through the holes in the tube base pins because there apparently wasn't much solder on the tube base pins.

[vortalexfan]

Originally Posted by Electronic M

L would have been the 1964 model year introduced in late 1963 (like car model years are).

The option code leters I don't actually remember which letter goes with which option. My 1959 Zenith had notation on the tube chart that made it obvious what letter was used for UHF and what was used for remote sets, but it's been over a decade since I looked at it and that set is covered in a mountain of junk presently.

The High Fidelity sets always had bass and treble knobs, sets without that option often had a single tone control.

Ok, thanks, I apologize for all these questions I'm trying to familiarize myself with how these old Zenith's work because while my dad's side of the family (specifically his grandparents) were big into Zenith products and thus my dad was as well I'm more familiar with the more modern Zenith sets from the 1980s and 1990s and the Zenith Radios from the 1930s-1960s, but this is my first time working on Zenith TVs from the 1950s and 1960s.

Aside from the old Meck and RCA TVs I've worked on and resurrected successfully I don't have as much experience with Vacuum Tube based TVs as I do Solid State TVs.

[vortalexfan]

OK, so I know that in the early days of FM Stereo Multiplex that often times manufacturers, like Zenith, Magnavox, Motorola etc. would design a radio that was "FM Stereo Compatible" meaning that it had a provision on the radio for an FM Stereo Multiplex Adaptor to be installed by a factory trained serviceman if one so choose to do so later on (specifically the old console stereos from the late 1950s and early 1960s).

I was wondering if that was also the case with the remote controlled TVs from that time period, that they made the TVs with a remote control sub-chassis installed from the factory if one chose to do so (the same was done with FM Stereo Multiplex early on) but then one could also get a TV that was "remote control capable" where the TV was provisioned from the factory so that a remote control sub-chassis could be installed later on by a factory trained serviceman?

If so I wonder if that was the case with my TV?