I posted quite a while back about my acquisition of a 1964 Zenith "roundie" that I suspected was a dog just due to the metal cabinet. Then I found out that metal cabinet sets are rarer than wood as wood was saved for whatever reason people used to save their broken TV and the metal ones got sent to the dump.

So with a grave need for space in my rather modest abode, I posted an ad in the V-K classifieds hoping to find homes for some rather nice radios and TVs that I have or had. I was disappointed at the fact that I was bombarded by inquiries on the Zenith, but almost nothing else. As a matter of fact I ended up junking or donating some really nice 50s consoles.

Anyway, I decided that since I don't have any other vintage color sets and remembering the absolutely beautiful picture that this set produced for a few hours before the color went out, that maybe it was a keeper. The thing that puzzles me is that all anyone talks about here are RCA this and RCA that with an occasional mention of other things, of which there are many AND more interesting in my opinion.

So, I am left wondering if it is worth the time and money to yank the chassis and throw in some caps, a color crystal, and replace the horizontal "efficiency" coil that seems to be dangling by its winding or other wiring. I just noticed that it is all wobbly when I put a finger on it. In previous posts some well informed members assured me that replacement would be the way to go.

I'm hoping that there are at least some Zenith fans/members that perhaps I can discuss issues with that may arise. As well there are some small cosmetic items that I would like to replace like the control door and the channel knob, which are there, but a bit tattered.

I have heard that these sets are great performers over the long haul. Supposedly RCA had a better picture (which I can't imagine from what I saw on mine), but Zenith had the quality build and many folks find them and are lucky enough to just plug them in and enjoy. I am not that lucky, but it might be an easy set to get going.
:scratch2:

Keep and restore your Zenith. It will not disappoint you. They are great sets.

We can start a "metal cabinet Zenith club"! :)

I just got done with a recap on mine, and now I'm on the hunt for a yoke. Here's a link to my thread.....

http://www.videokarma.org/showthread.php?t=259958

The picture doesn't show it well, but the cabinet on mine is almost a maroon color.

i have the same zenith metal 1964 ,with a perfect crt . i will be restoring this winter.

Fix it up. I was never a fan of tin-cans but you can always
do a transplant later on. Most sets back them were plane
Janes anyways with boxy cabinets.
As far as pix goes its a matter of taste. Zenith was always
my #1 set but the best roundie pix I ever saw was on
an Admiral of all things........

73 Zeno:smoke:

RCA's get a lot of attention because so many mfr's used the RCA design and key parts. Zenith will give a great picture... if the CRT is fairly good. Good luck and have fun!

seems like there are many more rca survivors than zenith.scant few here in columbus ohio.we rarely saw a zenoth roundie in for service.many rca sets but few zeniths.the best roundie picture was hands down the zenith sets.

seems like there are many more rca survivors than zenith.scant few here in columbus ohio.we rarely saw a zenoth roundie in for service.many rca sets but few zeniths.the best roundie picture was hands down the zenith sets.

A low hours, CTC16X with the original Hi-Lite CRT, was pretty hard to beat.
They seemed to have a better picture than their rectangular counterparts.
I had the last of the Zenith roundies, where I installed an RCA Hi-Lite CRT, in it. Talk about the best of both worlds. :thmbsp:

metal cabinet TV's are well suited for nyc apartments

Nice thing with the Zenith is that you don't ever have to worry about charred circuit boards. I like those metal cabinets if they're in nice condition, IMO easier to keep up that a wood cabinet. At least here in WI, wood fiber is constantly on the move, so the finish literally wears itself out from expansion and contraction cycles.

Mine's a "Double-First Cousin" to Tim's...I THINK mine's a '65, though..

DEFINITELY a set worth restoring and keeping!!!

I kick myself in the a$$ every time I think about how many of those metal cabinet Zeniths I junked because nobody would buy them in the 80s. Unlike so many of the other "tin cheapie TVs", some of those Zenith metal sets were VERY high-end; Space Command 600 remote, and the 'hi fi" sound with bass & treble controls. I think those were built as easy replacements for people who had big B&W sets built into walls, and expensive custom cabinets.

I also wish I still had any of the little Zenith metal color sets (14"-16").

Charles

DEFINITELY a set worth restoring and keeping!!!

I kick myself in the a$$ every time I think about how many of those metal cabinet Zeniths I junked because nobody would buy them in the 80s. Unlike so many of the other "tin cheapie TVs", some of those Zenith metal sets were VERY high-end; Space Command 600 remote, and the 'hi fi" sound with bass & treble controls. I think those were built as easy replacements for people who had big B&W sets built into walls, and expensive custom cabinets.

I also wish I still had any of the little Zenith metal color sets (14"-16").

Charles

Thanks to everyone for encouraging me to do something with my set, and I am glad to know that there are others here for me to communicate with if I run into issues and possibly to scrounge the cosmetic goodies that I mentioned.

One person mentioned never seeing Zeniths in for service. Well, I would say that the statement speaks volumes on which is the superior build. I have always heard that Zenith made pretty bullet proof sets as compared to the other brands and were often more service friendly if service were an issue. My set has seen enough action to have had a rebuilt C.R.T. installed at some point. Seems like it is a Magnavox and I seem to recall some folks talking down on Magnavox rebuilds. MY tube however is in good shape and as I said made one of the most beautiful color pictures I have seen after about 3 decades of dormancy to the best of my knowledge. So, that should work out fine.

Like Charles, I want to kick myself for all of these sets be they metal, wood or whatnot that I scrapped back in the 80s. I was in high school electronics back then and these and some pretty neat 50s black and white sets were EVERYWHERE. Heck we had a Predicta (junk) sitting in our donation area in the classroom that nobody cared about! They (older sets) were either free or pretty cheap and to me had much more charm than what was current at the time. That is what got me into the hobby really. Just growing up in the years when these sets were say in the 70s still in regular service, and then the 80s when people were moving on to other things. TV shops were glad to find a kid like me to take some junk out of their way. I have seen truckloads of 40s-50s black and white sets loaded for the dump. It would sicken me that I couldn't save them, but my father already hated the "junk" I was filling his house with!

Anyway, again thanks to all and when the time comes I will update this thread. I have to order the horizontal efficiency coil first and make a capacitor order. I already have the color crystal that someone here sent me to hopefully get my color back. I think I will replace the paper, bumblebee, or old reddish brown drops that may be lurking. I think the electrolytics will still be usable, for a while anyway.

there are many more rca survivors than zenith.Certainly true around here. I watch for vintage TVs pretty carefully, and the only color roundies I have ever found are RCA. Maybe things are different on the Right Coast where old TVs (and old things in general) are more plentiful.

Phil Nelson

We can start a "metal cabinet Zenith club"! :)

I just got done with a recap on mine, and now I'm on the hunt for a yoke. Here's a link to my thread.....

http://www.videokarma.org/showthread.php?t=259958

Hey, will you check you horizontal "efficiency" coil and see if it is rigid or sort of flopping around as if the stem is cracked or something. I have pretty much been reassured that I need to change this as I posted about being able to reach in there and noticed it being sort of wobbly. However, I have not had opportunity to discuss this with someone with the same exact set,

If you have already buttoned up the access plate on the bottom, then don't worry about it, but if not it can be reached pretty easily.

Thanks

Access plate on the bottom on mine is missing, so it's an easy check :)

What's it look like?

The metal cabinets are my favorite. The color circuitry can be a bit of work for someone used to RCA sets but the Zenith flybacks are way(!) more reliable.
The tuners on the early Zenith colors are great also!

Hey, will you check you horizontal "efficiency" coil and see if it is rigid or sort of flopping around as if the stem is cracked...
If by some miracle the coil is still intact, i wonder if one could rig some kinda non-metallic pressure clamp to keep it that way(?).
If doable, the same could be done to preserve those blue coils on the convergence board.

If by some miracle the coil is still intact, i wonder if one could rig some kinda non-metallic pressure clamp to keep it that way(?).
If doable, the same could be done to preserve those blue coils on the convergence board.

That is what I have been thinking. I mean it should simply be a coil of wire with I assume an iron, movable core. If the plastic case has just hardened and cracked leaving it wobbly, I would think something like plastic epoxy or super glue would restore the structural integrity. AND if nobody has noodled with the adjustment, no further issues should exist.

Now this is saying a lot coming from someone who is asking someone else to look at theirs as for all I know they might have been wobbly from the get go, but I doubt it. Just saying I know little about it. The only reason that I found the condition is that when I brought the set home the first symptom I encountered was no high voltage along with the horizontal output tube having a red glowing plate. Not a good thing with these sets. The evidently delicate nature of the horizontal/high voltage circuitry and it's proper set up is what gives me such concern.

Anyway, tube investigation proved that almost all of the related tubes to these circuits were shot. I replaced them and then the set cam alive and seemed to be stable other than an odd sort of horizontal interference line running about 3 inches in from the left side of the raster. Not a bar, but a sort of jagged line. This line was the only thing that was less than perfect with one beautiful color picture until as I have mentioned, the color went out to black and white.

I will never forget how neat it was when I first applied full service drop voltage to the set. You could sit and watch things come to life after decades of dormancy. The most interesting was the color, which I didn't really expect to be as wonderful as it ended up being. It started as a pure black and white picture and I was pleased by sizes and linearity being spot on. Suddenly a small area near the center of the C.R.T. began showing sort of a swirl of color which slowly grew until the picture was full color. I didn't even have to mess with the Hue or other adjustments! What a good feeling!

Of course the color went away faster than it came to life, but I see that as being a minor issue. It's the power supply and sweep circuits that I think need full integrity and immediate attention. That goes for all sets really.....:thmbsp:

Access plate on the bottom on mine is missing, so it's an easy check :)

What's it look like?

First, Horizontal Efficiency is stamped into the chassis on the control pot mounting flange near the end where the high voltage related tubes, cage etc. are located. There will be an obvious adjustment there which is actually horizontal linearity. Evidently "efficiency" is just Zenith's pet name.

So if you are looking at the adjustment end, then the business end is just behind the chassis steel. You can reach in from underneath and gently give this coil a feel to see if it is rigid, or if the winding portion which points straight out toward the front of the chassis is loose or "wobbly" as I call it. So, it is something about a pencil's diameter which is the adjustment shaft coming from the inner wall of the chassis and protrudes out a couple or three inches to a thumb sized winding.

Again, be gentle as the plastic in some of these old sets can fall apart pretty easily. We don't want your set to have a new problem! On the flip side, you need to know the condition of such things yourself. More than one person has told me that if this coil is indeed messed up, then you are looking at the H.O. plate (I think) or grid current problems that haunt these old color sets.

Anyway, let me know what you see, or feel, in yours. I really appreciate it. I once had a box of yokes for these sets that I had junked, but they are long gone now. Wish I had them; I would send you one!

Guess I got lucky....mine is like brand new.....

I think that if you'll be able to restore your Zenith, you'll have a great TV set! I have a wonderful roundie color Zenith Parkhurst, and it is really a great set!


However guys... :) I'm looking for a tv set too... I hope that you remember my post about the RCA Worthington. I have a nice Nordmende Spectra Color with four screens, one of the first series with tubes, that I could also use as exchange goods if somebody here on Videokarma would find a CTC7 Worthington (21RC899)... :yes:

Guess I got lucky....mine is like brand new.....

Somehow I missed your post. So yours is like brand new you say. That means I guess that it is rigid to the touch and not sort of springy like the shaft is broken or something. By "to the touch" I mean putting your finger on the top or end of it and gently attempting to move it.

Yep, and I'm actually REALLY glad that you bumped this thread. I came across this out of a Zenith color set that I parted out this past summer. I *believe* this is a spare to the one you're looking for, yes? If so, it's yours.

This came out of the set in this photo: http://www.videokarma.org/attachment.php?attachmentid=178795&d=1369873491

That one looks like the hoz hold coil.

The line in the picture is probably a barkhausen or snivet. (sp?)
Saw a few caused by hoz output tube. Dont remember any more
about them, think is was more common in the olden days.

73 Zeno:smoke:

That one looks like the hoz hold coil.

The line in the picture is probably a barkhausen or snivet. (sp?)
Saw a few caused by hoz output tube. Dont remember any more
about them, think is was more common in the olden days.

73 Zeno:smoke:

:) Hey guys ,

Speaking of Barkhausen , does anyone remember the little magnet gadget that was supposed to mitigate it ? Not the "Damper Rings" like the Audiophile guys now use , but more like something looking kinda like an ION trap , just designed to fit around a Horizontal output tube . In all my years of TV repair "back in the day" I recall seeing 3 or 4 of them , but never experimented with any of them for fear of having my fingers THAT close to a running Horizontal Output . I presume one was to rotate this about the tube till the raggedy picture edge went away , and then tighten it into position with a little thumbscrew .

...like something looking kinda like an ION trap , just designed to fit around a Horizontal output tube .

Those WERE ION traps...Most HO Tubes were about as big around as a CRT neck so it worked.

Yep, and I'm actually REALLY glad that you bumped this thread. I came across this out of a Zenith color set that I parted out this past summer. I *believe* this is a spare to the one you're looking for, yes? If so, it's yours.

This came out of the set in this photo: http://www.videokarma.org/attachment.php?attachmentid=178795&d=1369873491

Well, the set in the photo is a few years newer, but the coil could be the same. I have the part # somewhere here in another thread and in an email, but not right in front of me. On another computer actually, but I'll get it and post it. Is there a number on that one? Thanks so much for thinking of this!

No numbers on it at all. Cap that's across the two outer terminals is a .0011 @ 400V. If you think it'll work, just PM me your address and I'll send it to you. If it works, great! If not, no harm done :)

I took a good look at mine tonight, and as much as I hate to say it; I believe Zeno is right. That is probably a horizontal hold coil. Mine is yellow plastic and much shorter. Also, the winding conductor on mine looks substantially thicker.

Thanks a ton for the effort and the offer. Mine is definitely toast though. Originally I thought that just the mount or outer shaft might be compromised, but suspicions have always led me to wonder if the actual winding was still tight, or had it loosened up. It is definitely loose or springy and that would certainly not be good in operation.

So, I will find one of those, grab a few caps, and try out that color crystal that was given to me to get the color back and I should be good to go. I may just do the non polarized caps for starters. If all works well, it will be all cosmetics afterward. I would like to find a really nice control door and a better (nice) channel selector if anyone has extras.

picture of the channel selector please

If the plastic forms are of the same dimensions you could always get his coil remove the wire from it and rewind your wire onto a good form...It takes patience, but if the wire is thick enough the risk of botching it becomes low.

picture of the channel selector please

I will get one a.s.a.p. I am fairly certain that the same one was used for several years.

If the plastic forms are of the same dimensions you could always get his coil remove the wire from it and rewind your wire onto a good form...It takes patience, but if the wire is thick enough the risk of botching it becomes low.

I assume that there is an adjustable iron core to think about, but either way it goes I don't have any other forms. I am pretty certain that I can order one.

OK, I have an efficiency coil on the way! These things are going like hotcakes to somebody and from the standpoint of a retail purchase of an N.O.S. replacement, there seems to have been FOUR of these in the WWWorld! Wow! Moyer had two about a month ago and had quoted me so in an email. Thinking that I am probably the only person on Earth knocking at a supplier's door for obsolete beyond obsolete TV parts, I didn't react immediately. Should have because they are sold out! I'm thinking that these coils sat around in inventory limbo as long as I have been alive and then sold out two units in a matter of weeks. Interesting to say the least.

At any rate, someone gave me a link to another supplier who just happened to have two as well, but for $13 more. I figured I better jump on in this time or else I may never get this Zenith going due to wishy washy H.O. cathode current. So, as long as U.P.S. doesn't fail me I am good. Frankly, the guy on the phone at this place didn't seem like he cared at all if he sold something or not. Yeah, one of THOSE inside sales guys! Supposedly they no longer really sell to private citizens, so I was sort of out of line even asking to buy their product and have it sent to my house. or that's the feeling I got. He asked me about 3 times what company I worked for. Geez! I kept saying that I work for a company and I am an electronics tech for that company, but I am not buying the part for my employer. So anyway, he finally took my credit card and shipping info. He never read it back to me to insure accuracy, so I hope that works out. Sorry folks, I didn't mean to go on a rant. I am actually happy to announce progress on the Zenith. However, I did a stint once as Inside Sales for an electronics repair/supply place and we were trained to be polite, AND reassure the successful execution of the order through relaying back all of the key data. On the flip, you get a lot of tards most particularly in "parts" related sales. It's sort of the nature of the beast I have learned as I also did auto parts once which is a road that I don't even want to begin to go down here.

So, I throw in the coil and hopefully the crystal replacement for the color will work. That info is in some other thread that I wish that I could locate. I have a bag of common value orange drop caps which I hope will cover many of what I will run into. Might as well replace whatever is left, but I will probably keep the electrolytics. I'm not going to do a play by play with pics and all, but I will definitely try to throw in a few.

I thought about going and picking up that vintage RCA color bar, dot, crosshatch generator that is sitting at the antique mall for another $35, but supposedly you can get DVDs with everything needed for alignment which would be a lot easier. I love old test equipment which A. is necessary and B. is working. Can't say I would ever use old color TV equipment again as I prefer old black and white sets. So the DVD sounds like a plan!

I have an RCA generator that I think all it needs are the electrolytics , it seems to work but I have a newer b&k that's less then half the size and does the same things as the rca , I was hoping the rca had better color bars but its just like the b&k , neither produces the crosshatch and dots at the same time which is also a little disappointing , it does come in handy , I even use the crosshatch on black and white sets to get an idea of the linearity.

still no picture of the knob

mike

still no picture of the knob

mike

Sorry Mike, no picture yet. It's not a really big thing and as a matter of fact I took the knob that I have and a piece of scotch brite and it cleaned up rather well. I was surprised frankly! Now the little door that covers the controls is a different story. Mine has a few small dents and dings in it that are not going to come out. I would really like to replace that! Do you think you might have one of those if I could provide a picture?

And to everyone else looking at this thread, I got my "horizontal efficiency" coil in the mail the other day. Nice, solid N.O.S. Thordarson part. I need to get specifics on the setting of the coil which supposedly effects the horizontal output tube's cathode current. In another thread this is being discussed as far as running a remote test point for regular checks on what is supposedly a critical measurement on these early color sets. I recommended putting in a fuse holder to have the circuit protected AND as a breaking point to put an amp meter in series to make the measurement.

We (I) need to get specifics on what current measurement would be acceptable on my Zentih and figure out a good fuse size based on that. I hope to find that there is a more or less general fuse size that would work on most early color sets so that I can relay this information to others, or they will find it in this or the other thread.

I got the horizontal efficiency coil in the mail, but haven't started the project of putting it in yet. I am wondering if there is a way that I can install the coil and have it pre-set if you will, so that the current on the horizontal output tube is not crazy high. I guess I can go through getting a amp meter hooked into the cathode circuit which is evidently what needs to be done anyway to make sure that it's not too high.

But I read in another post someone saying that you want to get the current as low as possible and still have good linearity. With that being said, you would think that you could simply run a set and turn the coil down until you start to see the picture distort and then go slightly back up just to the point of having a correct looking picture. If this were correct it would be a heck of a time saver. Not to sound lazy, but I want to get the set up and running to get a better evaluation of what is going on with it, or not.

I do eventually want to put a fuse in the horizontal output circuit and that would give me a perfect place to put a meter in series with the circuit, but that's a bit down the road. Main thing is I don't want to throw this coil in and be instant red plating.

In my experience the correlation between horizontal image linearity and HO Tube cathode current is very weak at best on roundy color sets. When performing the adjustment I have not seen any change in linearity while adjusting current from previous tech's setting to the setting that would yield minimum current, but I have read that good linearity and current can be in conflict in sam's folders for some of my sets.

My advice would be to monitor the cathode current on the first power up after the change and as soon as it starts to stabilize adjust the lin coil for minimum current.
I would look at the slug position of the old coil and try to roughly achieve that in the new coil before power up.

Under a minute of redplating should not damage anything(it is when the fly begins to heat up that bad things happen). But I doubt the lin coil could produce redplating unless there were serious circuit problems.

If you seriously do not have a meter, there's a 'quick & dirty' way of dipping the efficiency coil. Connect a #44 bulb (which is rated at 250 ma) in series with either the plate or the cathode. Adjust the eff. coil for minimum brightness. The bulb should glow at signifigantly less than full brightness, indicating the current to be well below 250 ma., and in the "safe" range.

We used to carry a 'magic light bulb' adapter in the tube caddy for this purpose; just clip it in the plate lead of the tube. It was surprizing how many sets in the field were 'off the dip'. In the shop we always used a proper (analog) meter.

There was never any observable correlation between eff. coil setting and linearity.

Red plating of the tube should be avoided at all cost. It can kill the tube quicker than it can kill the flyback due to the tube's small thermal mass. I've seen HO tubes with holes melted thru the glass and the flyback was still good.

Thanks Electonic M and old coot88 for the ideas. I guess I know the right way to do such a job, but often there are 'tricks of the trade' that are guicker and/or easier, while being just as effective. I think old coot88's tip is one of those very ideas, for those without a meter at least, but like a meter the circuit still must be broken and the bulb wired in series.

As for me, I have one of the monolythic Hickok Model 209A "volt-ohm-milliammeters, which is primarily for show since I can't find the proper size lead plugs for the small leads which I may have one of, but I would need two for some functions. The lead that I have is brittle, but I could re-use the ends. I have the large screw in lead in good condition. I love the look of this unit and would like to put it to use some day, but that's likely another restoration in its self. I also have an old Simpson VTVM that needs calibration or something as well as a later solid state Simpson that works great. I like to take that one to work to confuse the 'super techs' and even engineers these days. That is what I will probably use for this horizontal output job since analogs supposedly do a better job at giving a good, steady readiing. Of course there is always a dime a dozen digital meter or two around. Mine is decent, but frankly I don't see a big difference between my KAL Equipment job and the ever so popular Flukes we use at work.

I think it is in another thread that this H.O. current is being mentioned and once I read to disconnect a pin that is grounded to the chassis and add a small value capacitor. Then someone else wrote that he didn't get a reading with a capacitor, but he did when he removed it. No doubt, with these threads you can't take every little thing to heart or you might never get a job done. There are too many variables like human and equipment error. But V-K sure a great place to get tips from the best of the best; many of whom were doing this for a job. That sure must have been a great time to be in the electronics profession as all of the home entertainment repair is gone. There are a few bench jobs in industrial equipment repair these days, but I will refrain from getting on that boring topic.

Thanks again folks! I'm feeling the Zenith exitement coming on! Once this coil is in place and with hopefully good results, I will probably be talking about getting the color back. I think I mentioned once before that someone sent me a crystal that is supposed to work as a replacement for the old type that supposedly often go bad. The new part looks almost like a blue disc capacitor. Hopefully this repair will be easy since the set had great color to be at least 20 years dormant, then it just went away completely to black and white, so probably not too difficult. I think its a capacitor frankly, but that's just because they are usually the problem with a long dormant set.

I had to remove the capacitor that is supposed to be added when doing the ma test on the cathode because the meter I was using wouldn't pass the current to ground with the capacitor there, once removed it went from the cathode to the meter to ground completing the circuit.

Tj,
If the HO cathode current was within spec before the eff.coil went springy, very probably it'll be within spec with the new coil once you dip it using the 'magic light bulb' method.:tongue: Does the HO tube look beat up with heavy black deposits inside the glass or other obvious 'burnt' looks? If not, it was probably running in the safe range.
RS still sells #44 bulbs (cat.# 272-1108).

Kramden66 mentioned using a cap with the meter causing an open-circuit condition (in the cathode leg). He mighta had the cap in series instead of in parallel with the meter.
I never used a capacitor with the meter or saw any need to, since the meter presents a very low (effectively nil) impedance. Like a near-dead short.

Back in the day, there was an adapter (Pomona?) you'd plug into the HO tube socket, then plug the tube into the adapter; it breaks the cathode leg, and two leads coming out of the adapter connect to your milliameter. Doubt if those adapters are still available today, though.

(EDIT) Just a thought.. i never done it, but it might be possible to use a
digital meter for cathode current by shunting it with a very large capacitor to smooth out the raggedy waveform. Several thousand mfd. might keep the meter from going nuts.

Hey kramden66, we have a good and valuable friend in old coot88! It's easy enough to tell that he did this for a living! I do it for a living as well, but I'm sure everyone has read enough of my soapboxing of the "dumbing down" of electronics. It's more or less a plug and play, or throw away world ever since the microprocessor was integrated into electronics. We don't really have a big need to know what used to be almost a given and really is just the fundamentals of electronics. Our knowledge base and training give us the capability and credentials to gain employment in the field; and yes I guess I take a lot of the knowledge for granted and I tend to forget that the average individual without some training doesn't know the difference between alternating and direct current.

Even we tend to forget aspects of the two types of current and their effect on capacitors as was proven by old coot88's reminder of a capacitor's behavior as an open circuit if placed in series with an ammeter and a DC supply. I hadn't really thought of it (or remembered), but it makes sense. With DC a capacitor is charged to its full capacity and then behaves like an open circuit with AC because of polarity reversal this charge and discharge cycle continue and the current continues to flow in the external circuit. There is no frequency with direct current, so there can't be capacitive reactance. X sub C = 2 x pie x frequency x capacitance if I remember right.

My HO tube doesn't look burned up, but when I first brought the set home there was no HV and the tube was red plated. It's been so long I don't remember all the specifics, but I think one of the tubes was damaged, maybe cracked. Seems like it was one of the tubes inside the HV cage. I replaced that and I think one other tube extenal of the cage that's related to sweep and gained HV and no red plate. It wasn't long before I discovered this coil and haven't had much power up time at all on the set. I didn't want to risk any flyback damage since I have read so much about it with these color sets which I typically never mess with, so my knowledge on a lot of the particulars of these sets is very limited.

OK, I installed the Efficiency coil finally. No real change, but there wasn't really a problem other than knowing that there was a broken part in the set that could cause damage to the set that could be avoided. I didn't work the set long as I still haven't wired in an amp meter and checked the cathode current.

I did notice a bit of hissing in the H.V. cage that led me to play with the slug a little. I could adjust a little and it would go away along with the on screen jitters that come with corona discharge. The discharge is very light; not a loud hiss or snapping like I have heard. I turned the H.V. adjustment down a little and it didn't make any difference. I need to get a meter on this puppy.

I have heard of moisture collecting in long dormant sets and noise from the cage being an issue until the set works long enough to dry out well.

Lacking a meter, at least get #44 bulb to dip the K current. Is there a RS store near you?
The dip point is very sharp, and if the coil is off dip, the current can be dangerously high and you'd never know it, even if the tube isn't red plating yet.
You're right about letting moisture cook off to see if the hiss goes away. But get the K current dipped first.

Lacking a meter, at least get #44 bulb to dip the K current. Is there a RS store near you?
The dip point is very sharp, and if the coil is off dip, the current can be dangerously high and you'd never know it, even if the tube isn't red plating yet.
You're right about letting moisture cook off to see if the hiss goes away. But get the K current dipped first.

I agree 100% on getting that current right. My Simpson meter should do the job fine. Or if I chose to use a bulb, isn't a #44 a standard pilot lamp bulb for vintage radio and TV? I need a source for a few of them, but I never would have thought about Radio Shack. I wouldn't think anyone would know what a bulb is that works there frankly! LOL! Again, thanks for REAL words of wisdom and good advice. It would be easy for many to overlook such an issue, but since I have addressed a real issue with replacement of the broken coil (which was floppy like a slinky), I may as well do the job right.

I never knew how important that cathode current was till I started working on my set and then was given the advice to make sure its ok , it was at 220 or 225 or something like that , I'd have to check my notes but it running like that was causing the fly to get hot after a while , now that I have it running at 200ma the fly doesn't get hot , I don't even think it gets warm , if it does its so low that it is tough to tell and is negligible , so get that bulb hooked up or even better the meter and make sure its not high , I was told I could probably take mine lower but the schematic shows 200 and the instructions say no higher then 210 , I didn't want to go to 180 as was suggested because the proportions are just barely right now , if it gets reduced anymore the only way a circle will still be a circle would be to adjust so theres is a gap at the top and the bottom and I don't want to do that.

is this cathode current issue important for the black and white sets too I wonder .

mike

The H output tubes in color sets (like 6JE6, 6JS6 etc.) are run at their absolute heat limit with no 'headroom' for overcurrent. That's why it's imperative to dip the current. Highest 'safe' current would be around 210 ma, with 200 preferable for good longevity. Much below 200 and you start getting width and regulation issues.
Tubes like 6KD6 etc. are beefier by design and can take more overcurrent, a requirement with the feedback-type HV regulation used in some Admirals.

B&W sets normally don't have these issues since the HO tubes run with adequate 'headroom'.

RS still lists the #44 bulb..
http://www.radioshack.com/product/index.jsp?productId=2102798
Incorrectly listed as "flashlight bulb".
Also listed is #47 which is more commonly used for dial lights, and is half the current. Cat.# 272-1110

These are foreign sourced junk but better than nothing.

I think I will use my Simpson 260 on this and go ahead and make a permanent and eventually fused connection point. Sounds simple; break the conductor grounding the cathode pin and run two pieces of wire to put the ammeter in series with the circuit.

I have a digital meter with the current fuses blown out of it, so I suspect someone without training in properly using a meter got a hold of that one and checked some amperes in parallel. I was on another thread last night and someone was talking about checking current with a volt meter hooked in parallel. There are quite a few fundamentals of using meters that perhaps we should do another thread on. I think it would be a good thread where the right people could explain the often superior nature of the analog meter. An elaboration on the further pros of the VTVM would be good too.

Also, I got a chance to evaluate types of capacitors on this (for my collection) newer set. I wanted to see what I might immediately want to remove as far as commonly known to fail types like bumble bees for instance. I didn't see any of those. Mostly I saw the old reddish brown drops which I hear are ok in most cases. The paper-foil is what I think needs to go and what I saw was several black plastic coated paper caps. I wonder if these are as bad as the bumblebee type, or even remotely as bad.

I think for now I will leave the multi-section cans alone as they are pretty tough old parts and sometimes I think they might be better than what you get from China. Anyway, what about those black beauties?

if in doubt check those black capacitors for leakage if you have such an instrument to test them, wouldn't hurt to replace them, they could be causing your color issue too.

as far as electrolytics go i've given up on trusting 40 year old or more electrolytics even multi section , I do have one set running on one original electrolytic in a multi can , its a 58 zenith and the reason is its a 475 volt cap , I didn't have any 500 volt ones to put in so I chanced it and it seems to be holding up , its tough to test the voltage because the set can only be removed by disconnecting the tuner with the two plug in plug out connectors running to the tuner and I really didn't want to remove the tuner just to test the voltage on that one electrolytic just to see if it has a higher then 450 volt running voltage and running wires from it would have been a pain too , down the road I may just replace it , its in the focus circuit.

awaiting the post that tells us the cathode current.

awaiting the post that tells us the cathode current.

Bad luck with meters lately. My digital junk has the current fuses blown. It was that way when I got it. I just forgot to get some more. Then yesterday I got out the Simpson analog; meter of choice and the batteries are dead.

Worry not, I will get this done eventually.:D

The H output tubes in color sets (like 6JE6, 6JS6 etc.) are run at their absolute heat limit with no 'headroom' for overcurrent. That's why it's imperative to dip the current. Highest 'safe' current would be around 210 ma, with 200 preferable for good longevity. Much below 200 and you start getting width and regulation issues.
Tubes like 6KD6 etc. are beefier by design and can take more overcurrent, a requirement with the feedback-type HV regulation used in some Admirals.

B&W sets normally don't have these issues since the HO tubes run with adequate 'headroom'.

I want to clarify this procedure before I go further as it keeps being mentioned, but I'm not seeing specific connection points for the meter or bulb. I am assuming that if I read the schematic and find the cathode connection then I can simply break the circuit at the solder terminal and connect one lead. The other lead should be going to chassis ground. Is there something that I am missing or is this OK?

...I can simply break the circuit at the solder terminal and connect one lead. The other lead should be going to chassis ground. Is there something that I am missing or is this OK?
Yup you got it. :yes:

If you use a bulb then inserting it between the top cap and the lead that connects there is a better idea as a series cathode resistance from the bulb could throw off the grid bias.

If you use a bulb then inserting it between the top cap and the lead that connects there is a better idea as a series cathode resistance from the bulb could throw off the grid bias.

This is true. But the 4V or so dropped by the bulb would be negligible and probably not noticeable except for a slight width reduction. For convenience doing 'dip checks' in the field, we put the bulb in the plate lead, using a little made-for-purpose adapter.

Looks like pins 4 and 10 will be the two potential places that I can break the connection and run two wires out to an eventual fused terminal. Then I can easily monitor this in the future by opening the two wires and placing the amp meter in series.

I saw a video where a guy showed two ways of checking the current on the tube. He was lucky enough to have some adapter that was made just for the purpose of cathode measurements. Also, he took measurements off of the much more easy to access plate cap, but he specifically used a stand alone milli-ammeter and stressed the dangers of doing it that way due to the extremely high pulses present there. Not sure why the old stand alone meter was any better to use than a normal analog meter, but that is what he used.

Lacking a meter, at least get #44 bulb to dip the K current. Is there a RS store near you?
The dip point is very sharp, and if the coil is off dip, the current can be dangerously high and you'd never know it, even if the tube isn't red plating yet.
You're right about letting moisture cook off to see if the hiss goes away. But get the K current dipped first.

I did it. I ran the two wires and connected my Simpson meter. At first the current was about 210 or even more. I was surprised at how much I turned the slug to get what I consider to be a small reaction, but I was able to get it down to about 200.

What I battle now (maybe moisture related) is some corona arching, or really more of a hissing. You can see it inside of the rectifier. This gives an interference of course on the picture which by the way is stable and linear. Sound is good. Just missing color now and the hissing. I have more than once been tweaking the efficiency coil or the HV adj and made the hissing go away, but it comes back every time.

My final concern is heat. I'm not used to color sets, and I don't know what is an acceptable amount of heat to have coming from the fly and the power transformer. In a perfect world they should stay cool, or cooler than other things like tubes. I kept shining a flashlight into the H.V. cage and looking at the fly for signs of melting wax or plastic. The metal around the cage was warm to the touch. I wish I had my laser temp gun from work! Now the power tranny was to me hotter than I prefer one to run, but then again I know these color sets pull a lot of current from the wall. I could put my hand on the power tranny, but after maybe 30 seconds it was getting a bit too warm. None of the lytic cans were warm at all, so that's good.

There was one of those brownish/reddish drop caps over in the horizontal section that to me felt slightly warm. I hope it was actually. Maybe it has something to do with my hissing. Oh, and there was one bumblebee in there. Need to get that out quick.

Say hey.:banana: if you got the K down to 200ma., great. The dip is usually much sharper than you describe, but if it holds at that value, what the hey. It wouldn't hurt to keep the meter on it for a while. Gotta luv the Simpson 260 huh?

It doesn't sound like you have any heat problem to speak of. The power xfmr will run pretty hot to the touch. The fly will get fairly warm. Sheet metal will warm up from radiant heat off the hot tubes.

The hiss sorta remains a work in progress.

Say hey.:banana: if you got the K down to 200ma., great. The dip is usually much sharper than you describe, but if it holds at that value, what the hey. It wouldn't hurt to keep the meter on it for a while. Gotta luv the Simpson 260 huh?

It doesn't sound like you have any heat problem to speak of. The power xfmr will run pretty hot to the touch. The fly will get fairly warm. Sheet metal will warm up from radiant heat off the hot tubes.

The hiss sorta remains a work in progress.

Indeed I love the 260! I have a Simpson 303 VTVM as well, but I need some new leads and the calibration is off. I tried calibrating it once, but something was still amiss. That's OK because the 260 is bullet proof. A few years back I was finishing up my electronics degree and one night while staying late the troubleshooting instructor came and got me and asked if I could help with a meter.

A fellow tech had sent his wife to class with his old meter to save a buck or two. Not even the instructor knew how to use it, but they figured out enough to set it to resistance and had gotten the manual out and found out that they had to zero the meter. Well, the meter wouldn't deflect but about half way. I knew that the batteries were dead. I told her that I had a digital meter that would suit her needs for the class as well as any other (which was true) and that I would trade her even. I told her that I was pretty sure that it was the batteries, but I wouldn't know until I changed them and I would take a chance on it in a trade. She was happy; I was VERY happy! Yellow case and all; like new.

Anyway, thanks for all the info. I feel better about a lot of things except the lack of dip point that you mention. I knew that there should be a more profound effect on the current while turning the slug. Actually, it was pretty close to begin with and turning the slug only brought it down a bit. On the hissing, I might double check the H.V. rectifier and regulator.

try moving the HV filament leads around. The insulation may be breaking down on them, and they run right next to the cage.

try moving the HV filament leads around. The insulation may be breaking down on them, and they run right next to the cage.

I turned the lights off to look at the source of the corona arc and all I could see was a blue glow inside of the rectifier tube. I don't recollect rectifiers glowing blue inside. I was thinking that they are normally dark. But I don't spend a lot of time looking. Anyway, I was just looking through the slots in the bottom of the H.V. cage since I have the set on its side.

Hope I can get it to stop. It's not an actual arc or loud snap, but more like a hiss which is still an arc of some sort, just not the really bad kind.

Do you smell any ozone from the HV area?

Maybe you have already done this, but I always clean the inside of the HV cage -- and everything inside it -- with isopropyl alcohol. Great for removing any grease or black soot. Even if it doesn't magically cure your hiss, it might make it easier to see what's going on.

Phil Nelson

Good job , now like stated make sure everything is clean including the pins in the tube sockets , also post when you start tackling the color issue.
btw the glow inside my rectifier is blue/green in color.
mike

Do you smell any ozone from the HV area?

No, can't say that I smell anything. Just hear the hiss and see the blue glow inside of the rectifier, and of course the resultant interference on the screen. I only mention the blue glow inside of the rectifier because I expected to see something when I turned out the lights, but that is all that I saw.

Perhaps it just wasn't in a viewable area. I have had a number of sets through the years to have sharp solder joints or whatnot causing arching, not a hiss, but actual arching. Seems like a long time ago I had an old color set like this that was doing this and it was just moisture around the H.V. lead to the C.R.T. Perhaps I should check that just to be sure. They are in close proximity, so maybe I mistook the sound's origin.

If you have a length of flexible plastic tubing, you can use it as a sort of stethoscope to track down the source of the noise. Sometimes it's surprisingly difficult to pinpoint a noise source.

Phil Nelson

A HV Rectifier tube that is glowing blue is getting gassy. 3AT2's are cheap and hopefully you have some spares to compare. Gassy rectifiers will take out flybacks!

If the HV rectifier is gassy it will run hot. See if it feels inordinately hot (after you discharge CRT of course).:D

oops on my end I was referring to the 6BK4

I seem them give off a ghastly green around elements on those when shunting a lot (dark screen).

also post when you start tackling the color issue. mike

Just a side note, I have had my eye on a certain notorious for failing "bumblebee" capacitor for a swap out just for general purpose. But before doing that I wanted to see what circuit that it involved. Turns out that it is a .01 600V cap (C117) that looks to be in parallel with what looks like 3 grids maybe inside the c.r.t.

So, I'm missing color but I don't think that this is the cap that would be one that would take it out leaving behind a good black and white picture. I probably still should get rid of the cap just based on the failure rate. I guess right now I am in the stage of repairing the set as opposed to just jumping in there and replacing every cap with no regard for actual troubleshooting. But even when I get it right I do plan on replacing most of the caps. I may keep the multi section cans as I have found them to be pretty darned tough.

Yesterday I turned the set on to see if I could find a lower dip point than the slightly over 200mA (more like 210) that I measured. To my surprise I looked at the screen and the color had come back, nearly perfect. But it didn't last long and then it was gone.

At least I know that whatever is going on is probably something pretty simple. I cleaned all of the tube pins and sprayed the sockets when I first brought the set home, so it may not be THAT simple. I need to check the color related tubes again for shorts and also that H.V. Rectifier for gas since I still have the aggravating hiss reeking havoc on an otherwise crystal clear picture.

And B.TW. I disconnected one end of that .01 bumblebee and it measured dead on with a D.V.O.M. capacitance tester, so I just tacked it back in place. I know that it along with the other brown drops need to go if I am to use the set regularly. As I stated before, I sort of like doing the repairs and learning something rather than shotguning a bunch of new caps in. Indeed, my way is probably much more trouble than the shotgun method of repair by luck. Especially with the lack of some useful equipment like a very badly needed oscilloscope.

Well, tonight I went ahead a got rid of one of the two "bumblebee" caps. It's the .01mfd @600. that I mentioned previously. If anyone has a schematic, it's C117 and looks to be in parallel with Red, Blue and Green G2s. Like I said, the old one measured fine, but I don't trust digital capacitance testing, so I just got rid of it with a spare .025. I hope the value change is not a problem.

I'm still wondering where the "hiss" and related picture distortion are coming from. It's in the cage for sure and it goes away periodically and the picture smooths right out. I haven't done a lot like test the tubes which is the obvious next move, but I just don't think it's tube, but Lord knows I could be wrong on that. I wish I knew what the fly should run at temperature wise. I can get a laser thermometer & check that out. I might luck out and find a sharp solder joint or something inside that cage.

OR, could this be moisture? Anybody ever heard of that? I know that moisture causes temporary problems with flybacks. Is this one of the symptoms?

First thing is first on a HV corona/arcing issue (or a restoration for that matter) clean the inside of the HV cage including all parts inside as good as you can without breaking anything(conductive dust and gunk can cause all sorts of arcing/corona). After the cleaning if the issues continue run the set with the HV cage open and or partially dismantled and look for arcing/corona in a dark room with the set on. Once you locate it a picture of the area it is coming from will tell us what it is and how to advise you to fix it.

First thing is first on a HV corona/arcing issue (or a restoration for that matter) clean the inside of the HV cage including all parts inside as good as you can without breaking anything(conductive dust and gunk can cause all sorts of arcing/corona). After the cleaning if the issues continue run the set with the HV cage open and or partially dismantled and look for arcing/corona in a dark room with the set on. Once you locate it a picture of the area it is coming from will tell us what it is and how to advise you to fix it.

Thanks E.M., that sounds like the logical thing to do. I am sort of jumping the gun I guess as I have the set in a tight spot in the kitchen sitting in the floor on its side doing all the work I can do without being able to move it around much. I guess the good thing about a corona/arch issue is that you can see it in most cases. Removal of the cover and testing the H.V. related tubes will be the next step.

I want to be sure that the fly is running as cool as it should. The ammeter remains connected to the cathode of the H.O. tube, so I can watch for any issues there. I need to run the set for a long enough duration to let things sort of stabilize as they often do. Flys are supposedly notorious for collecting moisture, but I don't really know the symptoms of moisture in a fly.

This set is so unpredictable! I was pleasantly pleased when one day I hooked up a VCR/DVD combo and actually had a clear picture WITH color which had disapeard early on. Next go around or two I used once a stand alone VCR and also an RF converter to try a stand alone DVD player.

Now I have this awful blurry picture with no color at all. The picture has about 4" missing from the top and oddly it will periodically and slowly fade to almost black making you think about HV problems (as I still have the HV hiss and related interference line that it creates on the far left of the picture, top to bottom). However, you can switch to an unused channel and the raster is bright and full as any TV should be.

So I am thinking something in the video or AGC circuits. Any other suggestions? Really this is all dumb when it all could be avoided by replacing the caps and probably having a good running set. Just don't have the time and I hear of so many of these Zeniths more or less working as found. Really, this set is real close to working all things considered. Good sound, full raster etc. Just the HV hissing, video issues, and color. The color can't be far from working fine as I mentioned the one day that everything was dead on pretty much with the DVD/VCR combo.

You really should track down that HV hiss. If it has bad enough arcing or corona it can affect HV stability and cause things like the flyback to die....

If you can't see the problem then get some rubber or plastic tubing, put one end in your ear and probe around the HV cage listening for strongest hiss.

The hiss is very, very light which is why I don't refer to it as an actual corona arc, but I guess any hiss is some sort of arc really. Sometimes it clears up on its own. I tweaked the HV adjustment once or twice and it would go away. This was not at an extremely high or a low setting. Just sort of a sweet spot, but it always comes back. You would think that an arc would be significantly worse with a higher voltage.

I shouldn't be messing with that anyway as I don't have a HV probe/meter, but I know approximately where it was set before. I need to find a probe to set that properly. I agree that I need to find the source as the set will never be up to par with that and it's distortion on the screen.

Again though, nice bright raster until a signal is introduced and then it is blurry and sometimes fades to nearly black as if there were HV trouble, but then you can go to an unused channel and everything is normal.

?...Again though, nice bright raster until a signal is introduced and then it is blurry and sometimes fades to nearly black as if there were HV trouble, but then you can go to an unused channel and everything is normal.
Does the overall raster size appear to 'breathe' or 'bloom' during the fade-to-nearly-black interval?

Does the overall raster size appear to 'breathe' or 'bloom' during the fade-to-nearly-black interval?

No, not really blooming as I have seen many times; simply fading to black and then it comes back. Now I can say that recently (probably said before) the picture is out of focus when it is there and appears to be bloomed with the top few inches cut off.

Somehow I think a lot of this may tie in with that hissing in the HV cage because it stops sometimes and things are a lot better, but I have had a much better display in the past even with the hissing which only seemed to cause a bit of distortion on the picture and a faint Barkhausen line to the left.

What throws me off is that no matter what I can go to any unused channel and the raster is bright and full with only a hint of the HV distortion when you look real close. That's what I just don't get. I powered the set today in a dark room and noticed a fairly bright blue glow inside the HV rectifier. I'm not sure if that is normal or not. I was thinking that HV rectifiers are normally just dark for the most part. Perhaps the rectifier tube is the problem. I have tested it, but not swapped it. And as we all know tube testers are not testing under real world conditions by any stretch.

Thanks for keeping up on this. I don't have time for a full restoration job and with most all other circuits working well, I don't think that an initial repair of the set is way out of line. If it were a 40s or early 50s set certainly, but these 60s sets can go with a little help in many cases.

...I powered the set today in a dark room and noticed a fairly bright blue glow inside the HV rectifier. I'm not sure if that is normal or not.
Definitely not normal. If the glow uniformly fills the entire space inside the tube, it indicates a gassy condition. And the tube will usually run abnormally hot.
I was thinking that HV rectifiers are normally just dark for the most part. Perhaps the rectifier tube is the problem. I have tested it, but not swapped it. And as we all know tube testers are not testing under real world conditions by any stretch.

In the case of a HV rect swapping with a known good one is the only real test.

Definitely not normal. If the glow uniformly fills the entire space inside the tube, it indicates a gassy condition. And the tube will usually run abnormally hot.

I wouldn't say that the entire envelope is filled. By looking up into the cage from below you get a good viewing angle of the rectifier. The glow is inside the thimble shaped portion (plate?)

I want to add that I didn't even realize what kind of an expert is helping me here. I have seen some amazingly well done videos by you on Youtube. It started when I was looking for and acquiring an old tuning eye capacitor tester so I can properly test my old caps. I ended up with a Heathkit C-3, but I am completely jealous of the out of this world unit that you demonstrate in a video. I can't recall the brand, but it had voltage and current meters and you give one heck of a demo!

Also, I remember you admiring your Hickok 209-A VTVM as one of the best pieces that you had on hand. I have one that I really want to get going. Like most older equipment I imagine I will have to replace a lot of capacitors to get it to function well. As it stands nothing about mine is accurate.

Glad to have you on my side in this Zenith project! Maybe I will start a Hickok 209 thread next!:thmbsp:

TJ,
'Fraid you've got me confused with confused with another person. The fella posting the cool videos is not I.:no: Perhaps he could chime in and say Hi.:wave: (Hey that's a po'm.):D

Regarding the problem with your set, in a shop setting the very first move would be to replace the HV rect, to eliminate that as the source of the problem.
But barring that, feel the tube after a few minutes' running. A good tube should remain just a little warmer than ambient temp. But if it gets sizzling hot that would indicate a problem.

TJ,
'Fraid you've got me confused with confused with another person. The fella posting the cool videos is not I.:no:.

Oh, OK; sorry about that! There is such a person who uses the same screen name as you and bears a plethora of knowledge.

Anyway, I think (HOPE) that I have a sub for that rectifier in my much too large collection of tubes. I started a thread in the classifieds looking for a HV probe/meter so I can properly set the HV. So far only one person has responded and he has something that I can connect to my Simpson analog VOM, but it maxes out at 25Kv which is (I think) where the HV should be.

If it is indeed 25Kv, then I could use the instrument, but would need to be careful not to peg my meter if the voltage were too high. Just turn it down and work up sounds like a plan.

...If it is indeed 25Kv, then I could use the instrument, but would need to be careful not to peg my meter if the voltage were too high. Just turn it down and work up sounds like a plan.
Even if goes to 30KV, it ain't gonna prang the meter movement any moreso than turning the R zero adjust overscale.

MAJOR score today. I went to the only place left around here that ever repaired TVs. The owner sold me a B&K HV probe for $35. Also, they still have a room full of tubes, so I grabbed a horizontal output tube and a HV rectifier for beans. I haven't had time to try the stuff, but my HO tube showed shorts on my Hickok 6000A. Perhaps that is the cause of these issues. I will know soon. Very happy with the finds! :thmbsp::thmbsp:

Well, I put the new rectifier in and the situation got better, although the horizontal lines at the edges (about 2"in are more pronounced). The lines are adjustable with the hold control. I used my new probe to adjust to 25Kv. I did it with the brightness down. Not sure if that is the correct method, but it did OK.

IF I can only figure out what is going on with the video and color I would have a decent working set. The lines that I mention I want to call Barkhausen lines but they run from top to bottom, not across. There is a Youtube video where a guy displays issues with HO tubes and Barkhausen lines and sure enough there are lines as well as bad video distortions which is what I have. The picture is not clear and has worms running through it; no color. I guess this is getting to be a good time for pictures. I never tried the new HO tube that I bought as Hickok 6000A (one of the best) does not test these tubes well at all. They have you jump the cap to pin #2 of the octal socket (crazy)! The meter slams and the fuse warning light comes on bright. Also it shows shorts, but so does the new one. I'm afraid that the tester will damage the tubes, so I used my cheap Accurate Instrument tester and they both test the same. The used tube has been red plated a few times and you can shake it and fell rattling. That can't be good.

Whatever is going on is somewhat intermittent as a couple of weeks ago I momentarily had a clear picture AND color, but that didn't last long. I guess this is why people just recap sets and not battle them. I'm pretty stubborn with this one as I know that it is very close to working decently. I haven't messed with color sets much, so I am a little weak on many issues with them.