Yours doesn't have sensor safe on it. :tongue: :D

I have one tube that was done in the red several years ago that is still holding on. That tube has probably seen at least 80 hours of use with the red. It started out in my Moto 21CT2 as a replacement for the necked 21AXP, then I got a CTC5 with a good AXP and swapped the CRTs between the two, then I found another mediocre AXP and stuck it in the CTC-5 and since then the permatex RED 21FBP has been sitting waiting to go into a Packard Bell when I get to it.

I just did another 21FBP22 with the red yesterday since the last one did well.

But it doesn't say, "Sensor Safe".

I don't think there is that much corrosion difference between the two. Either is probably OK. If there is a difference it would be hard to prove because any corrosion difference could take decades to show.
Certainly you don't want to use the type that smells like vinegar ( ascetic acid) as it cures.
The black type has a very strong grip on surfaces, more like a glue.
The gasket maker is something that could be removed and re-made.
Either one requires the surface they are applied to be cleaned well with solvent like strong alcohol or acetone to remove any oil, etc.

You want to use ammonia to clean the mating surfaces. The factory glue responds best to ammonia and if you don't clean the factory glue off it will continue to degrade and undermine anything glued to it.

OK, my parents have some ammonia in their basement, I might have to borrow some.

But no one answered my question about the electrolytic caps in the big Zenith TV, I had asked if it was ok to just replace the bad sections of the multi-section caps and continue to use the good sections of the multisection caps, or if I should just replace all of the electrolytics and be done with it?

If you find the caps are full-on open with very high ESR, I'm not sure they would reform. It the old days, I usually just bridged a new one across it to see if issue would go away. More importantly, if the cannot charge up to rated voltage using a high-impedance cap tester with an eye tube, just disconnect those sections and replace one cap as needed.

Often just the half-circle (usually the highest value) cap section is suspect as it gets the full DC supply initially before the tubes warm up and begin to draw current.

I usually find one out of four open, showing very high ESR, almost always on the lower values like 2, 5, 10, 20mf etc. Even if ESR is low, you may still find that cap becomes leaky at rated voltage. It probably went bad long ago but a good set like this Zenith might not show symptoms.

Well the Main Power Supply Filter Cap (which in these Zenith's, at least the ones I have) is just a single section can seemed to measure what I'm assuming to be either open or shorted as on my ESR tester (one of the small digital readout ones that you would get as a kit online either fully assembled or you would have to assemble yourself) was showing 29pF on the readout with no ESR reading or anything.

The sections that tested good had ESR readings of .77 ohms or less, (those were on the two 4 section cans) and the one 4 section can that had one bad section the bad section showed a lone 29pF readout on the display and no ESR readout, the one that had 2 sections bad also read 29pF and no ESR reading on the display, which like I said I'm assuming that means the sections are open or shorted.

The paper caps in the TV all read pretty close to spot on MFD value wise, but that doesn't mean anything, they could still be leakier than all get out.

I did that on my 29JC20 and it shorted or opened a section every 2 weeks after that until the 3rd time I gave up and changed them all.

It is best to just go ahead and change them all rather than go through the trouble of having to remove the chassis again. Caps are really not that expensive compared to other things that sometimes have to be replaced.

In your question about the flyback cover that is falling apart, you will have to do something to support the centering magnet rings at the very least.
There is a thread somewhere here that show how someone built up a replacement cover for another type of set.
I have also seen a post about someone else that made a new cover using a 3D printer for another set.

You mean the yoke cover? Because that's what fell apart on the 23" Zenith of mine, I unfortunately don't have access to a 3D printer, let alone the design plans for this TVs Yoke cover.

Ah! Yes I meant the yoke cover. I've got to make sure I get my morning coffee before I reply next time.
I'll see if I can find the thread where someone build a cover from scratch. I think his was a RCA. It wasn't simple, he used plastic pipe, thin plywood, etc.
EDIT: OK, it was a Philco Seventeener. The yoke stuff starts at post # 93. You probably will have to use different materials. I see someone did something similar that was all plastic.
http://videokarma.org/showthread.php...Rigotti&page=7

OK, so I'm trying to come up with a list of replacement capacitors to order for my Zeniths and the 23" Zenith is giving me problems because there's three Bumblebee Caps in there and when I tried entering the color code from those caps into a capacitor color code decoder app online it came up with 2.2 MFD on one of the capacitors and the other two came out as 4.7 MFD capacitors all of them of which were 10% tolerance and 400 WVDC.

But that doesn't seem quite right when compared to other capacitors nearby which are all under 1 MFD (.15 MFD or less.)

I looked at the parts list in the Sam's and they do list a couple of capacitors at 4.7 and one at 2.2 but they don't have any voltages listed for them and they don't show if they're paper caps or if they're Mylars, or Ceramic Disc Caps in the description and the 4.7 and 2.2 values given for those capacitors don't say whether its MFD or MMF.

Any Help would be appreciated.

Find out where these capacitors are in the schematic. Sams should have the exact value next to the capacitor's symbol. Read Sams footnotes to determine if these capacitors are MF or MMF. Usually, if the value is less than 1, it's in MF. If it is more than 1, it's in MMF.

The odd part is that the Sam's that I have (I bought a PDF download from Sam's) doesn't have the schematic for the main TV Chassis, just the tuner and the remote chassis, nothing for the main TV Chassis though... at least not that I could see.

:saywhat::eek: Should oughta read: "if less than .001 mf it's in mmf (micro-microfarad, aka picofarad or pf)

Microfarad or mf (sometimes written mfd) = one millionth of a farad
Micro-microfarad or mmf (sometimes written mmfd or pf) = one millionth of a mf.

Typically values below .001 mf are in mmf/mmfd/pf.

And let us not forget the new nomenclature that seems to be in use everywhere today: the nanofarad or nF which is one thousandth of a microfarad.

OK so I figured out what those Bumblebees were, they were .022 μF 400 VDC
and 2 .047 μF 400 VDC capacitors so I ordered some 630 VDC replacements of those capacitors, since they were using the same capacitance values as the modern caps use.

I've already got the two .047 MFD Bumblebee caps replaced in the TV (I actually had a couple of replacement caps laying around of that value that I forgot I had laying around) so now I just need to wait for the rest of my capacitors that I ordered to arrive, which I'll have to work on this more when I get back from my trip.

OK, so I got some more of the paper caps replaced and I went to power on the TV to check to see if I was getting anything on the Screen, and for some reason the set isn't getting any power, the tubes aren't glowing, no static out of the speaker or anything, and I didn't touch anything related to the power supply all I did was replace some of the capacitors (which I took the old ones out and installed them like they went in originally when there was room for the soldering iron to fit without damaging surrounding components.)

Any ideas as to what could be causing this issue? I know it powered on fine before I started replacing components, there is a circuit breaker on the front of the TV, and I know those are notorious for going bad, could that be part of my problem?

Circuit breakers can sometimes beco sensitive to mechanical vibration. I'd ohm it out and if necessary wiggle it and or push/pull the button a couple of times before condemning it.

Sometimes power switches will get sticky and or dirty and the contacts will stay open or closed despite the handle being in the opposite state.

Another possibility is if you accidentally shorted the heater wiring there's often a fusible link (piece of magnet wire thinner than the rest of the wiring designed to burn open like a fuse if there's a short).

There's enough that could go wrong that no definite conclusion can be made from available info.
What I typically do in cases like this is pull the chassis and do bench resistance and voltage tests.

I monkeyed with the circuit breaker and sure enough it came back to life. But I'm still not getting a picture or raster on the screen, and still no HV.

Measure the voltage on the grid and screen grid of the horizontal output tube.
The grid will tell you if you're horizontal oscillator lives and the screen can give info on whether there's issues on the flyback side.

The entire horizontal system has to work for there to be HV. It's typically much faster to troubleshoot that system than it is to shotgun parts (though replacement of paper and lytic caps is probably wise).

I'm not sure if it's the vertical or horizontal oscillator that's running but one of them is running for sure because I hear a high pitched whining noise coming through the speaker.

The Flyback Transformer looks like its in good shape yet, it only has one wax drip underneath it inside the HV Cage and that's it.

As far as measuring the Voltages on the Horizontal Output Tube, I thought you weren't supposed to test that, because of a chance of frying your multimeter?

Its possible the horizontal oscillator is running, but there are a litany of other things that could cause squealing through the speaker. Including self-oscillation in the IF system. You should take measurements to check.

There's only one terminal on that tube that can harm a meter: the plate. The plate is always the top connector on the tube. Measure the other terminals (the ones on the bottom) and your meter will be fine and you'll know more about why there's no HV.

While it is nice your flyback looks good, looks are not conclusive. I've seen scary ones work fine and really nice ones that are shot.

Also if you are running it for more than 30 seconds after warmup and there's no horizontal osc you can potentially damage both the flyback and H output tube.

Ok, thanks. I've only ranthe TV long enough to check for a picture on the screen, after I saw there wasn't anything on the screen I immediately shut it down.

OK, so the Control-Grid (Pin 3) was 125 VDC and the Screen-Grid (Pin 2) was -0.5 VDC when I measured them, and the Horizontal Output Tube is a 6GE5 12-Pin Compactron Tube, so I'm not sure what that means in regards to the condition of the Horizontal/High Voltage Circuitry goes.

Measure voltage on pins 2 and 3.

Do NOT measure pin 7.

Generally a penthouse tube's elements go: heater, cathode, control grid, screen grid, suppressor grid, plate (pin mapping is often random). And if grid is used without screen or suppressor in the sentence then control grid is meant. If you looked at the tubes pinout/datasheet you shouldn't need an explanation of which pin is which. The first datasheet hit on Google has a plenty good explanation.

See my updated comment in post 107.

Control grid should be negative (usually in the -50V to -75V range). Refer to the schematic for correct value. If control grid isn't sufficiently negative the osc is dead or it's signal isn't getting to the output tube.

Screen grid should be positive in the 75 to 200V range. Again refer to schematic.

Part of me wonders if you have the two mixed up.... regardless it looks like you're missing horizontal oscillator signal and or the osc isn't working.

If the screen grid is truly negative like that it means that the damper, flyback fuse or flyback is open. The screen grid voltage drops below spec when the plate isn't drawing current and the screen acts as a stand in plate...If it has dropped that low then the screen current is dangerously high and the tube may already be damaged. It could possibly get that low if there's no osc signal at the grid and the plate is not drawing current from an open circuit.

Well I've just about got this TV recapped I've replaced all of the paper caps except for 2 of them, and then I've replaced all of the electrolytics except for 2 of them, and its because they were values I didn't have on hand, but I have them on order right now.

One thing I noticed is that one of the electrolytic caps was in the Boost circuitry and that was one of the caps that measured bad when I measured it with my ESR meter, and also the main filter cap (which consists of 3 80 mfd 450V caps in series) also all measured bad which are part of the B+ voltage circuitry which might of explained the low voltages on the Horizontal Output Tube.

Also I noticed there's a neon bulb under the TV Chassis near the Horizontal circuitry, what is the purpose of that neon bulb?

Without the schematic Infront of me I can't tell you for sure what the neon does. Zenith did use them as spark gaps on some monochrome sets. It could also be a voltage reference or a couple of other things.

I got a screenshot of the schematic for my Zenith 23" TV showing where the Neon glowbulb is in the circuit, and from what I can see, it seems to be in the Vertical Deflection Circuit, but what purpose it's serving there I'm not sure, but I do know its not serving the purpose of spark-gap service because there's a couple of wires on the picture tube socket serving that purpose, as can be seen on the schematic.

See the schematic excerpt below.

Well I finished recapping the TV and went to power it on and I heard the sound of what sounded like the high voltage coming up but instead of it being only for a few seconds it was for the whole duration of the warmup time and there was no audio, and then I saw smoke.

That's when realized that I installed the wrong value of capacitor in place of C3B which is the filter capacitor for the output transformer, which was supposed to be a 10 MFD 450VDC capacitor, and instead I put a 100 MFD 63 VDC capacitor in its place, which that capacitor is supposed to be filtering the 270V line going into the output transformer.
So because I put the wrong capacitor in, the 100MFD 63VDC capacitor couldn't handle the 270V going into the capacitor which was basically overloading the capacitor and causing it to vent (thankfully I shut it off before it vented.)

And Unfortunately I don't have a 10MFD 450VDC capacitor in my stash like I thought I did (well I do but its an old Sprague "Atoms" capacitor that is really large and it wouldn't fit very easily in the already tight space under the TV chassis), so I'm going to have to order one.

You didn't show enough of the circuit to be able to determine what signal is driving the neon bulb. I suspect it's some sort of horizontal blanking signal, not a vertical signal.

Here's a better shot of the schematic showing the Neon Bulb and the circuit its in. It looks to be part of the Horizontal circuit as you said, but I'm not sure what its purpose is in the circuit.

See picture below.

OK a little update, I did end up using the Sprague capacitor I had, and I did actually have room underneath for it after all, but just barely.

Do you know how I would go about bypassing the circuit breaker on this TV?

I'm asking because everytime I move the TV it trips and to get it to reset I have to go under the chassis and reset it with a screwdriver (with the unit unplugged of course) because the pushing the red button on the circuit breaker doesn't do anything anymore (I've tried jiggling it rotating it, pushing it, pulling it, etc. and it doesn't reset the breaker).

Well, , , that's an easy question, if you suspect the breaker has gone defective, you replace it with a brand new one of the exact same rating :thmbsp:

Any other talk of "bypassing" bypasses all kinds of safety and common sense, so I have no input on that.......... :rolleyes:

When I was referring to bypassing the circuit breaker I just meant temporarily for testing purposes to check my work as far as my capacitor replacement went.

Private Pyle !!!!!! What part of this do you not understand !?!?!?!?:twak: