A Confession

[Hagstar]

Well after working on my RCA ctc4 Seville a whole year nearly I finally got a good picture. I made a nice repro back for it and added "dressing" coats of lacquer to minimize the heavy scratches. I was ready to put it in the living room- AND THEN THE FLYBACK BEGINS ARCING. I encased it in electrical tape and 1/4" of silicone which worked well- for a few hours. Then high voltage plummeted- the arcing appears to have been merely hidden now it reads 10K ohms instead of 550

Okay I admit I was running it at 217 milliamps current as that was as low as I could get it (high voltage about 22.5 kV) and I had no idea the RANGE was 170-220. And I know very well how impossible these are to find. BUT of all places I figured I let it be known here I'm very happy to buy a parts chassis to get one. This was/is going to be a major centerpiece and I'm willing to invest, and it will help me remember to ask here about the amperage rather than rely on the original service manual. This is a late model chassis I have currently I'm fairly certain- #2746056 and still has the original steel CRT.

No hurry-I can't make the convention this year but any leads from there too appreciated- THANKS!

[TUD1]

Aw man. That's such a nice set. I quite like the looks of the 21-CT-55 series. I know how it feels to finally get something working and then it goes and breaks again out of the blue. I hope you find a good flyback!

[Hagstar]

Thanks, it sat outside on a porch 1980-2008 and this was a bit hard on components.

[miniman82]

There's no 21-CT-55 series, just one set. The 4 had different models, this is one of them. Fwiw you might be able to unwind the HV doughnut and use a tripler off the HO tube plate cap, the museum did something like that and it worked.

[walterbeers]

Darned, what a disappointment after all the work you have put into it. 217 MA might be a little high, but not excessive by any means. My 21CT55, (CTC2B) about the lowest I could get it was around 210 ma. It still works great (at least for a set that old), but I'm always afraid of leaving it on for hours, as I don't want the same thing to happen to it. Heat and humidity are killers of those RCA flybacks. Good luck in finding a replacement. Keep checking the different sites on the web, surely someone has an old chassis somewhere that has a good fly on it. It seems to me that there was someone around my area (Omaha), that had either a CTC4 or CTC5 with a necked tube that was in pretty bad shape. I'll ask my friend Jamie if he remembers anything about who has it.

[Hagstar]

Originally Posted by miniman82

Fwiw you might be able to unwind the HV doughnut and use a tripler off the HO tube plate cap, the museum did something like that and it worked.

I AM SO DOWN FOR THAT BLESS YOU. Will investigate, thanks.

EDIT- Can't find info on museum website though so far.


John H.

[ohohyodafarted]

As my good friend John Folsom (aka Mr. Early Color TV) told me when I first got into this hobby......."It's all about the spares" I am sure there are people out there who probably have a good used spare, however the minute you sell your only spare, that is when you will need it to fix one of your sets.

It is a rare part indeed. Attached are photos of my NOS spare, the improved version. (probably worth it's weight in gold)

You are correct, your Seville is a "late production" set. However that does not necessarily mean that the flyback is the new improved version. The original flyback design was very problematic. Many many failures. That prompted RCA to redesign the flyback and the replacement was far more reliable. The original version flyback was stock #100409 and it will have the RCA drawing number 1106237-1 stamped on the frame in black ink letters in the same place you see in the photo.

The improved flyback is stock #101959A and will have the RCA drawing #1106237-2 as shown in the photo of my spare.

I have discovered over the years, that you need to buy backup sets that are in poor condition, so that you will have a source of spare parts for the sets that are worth saving. I do not subscribe to the notion that ALL sets should be saved. If a set is a POS then use it for parts and canabalize it so that a nice quality, or rare set, may live again.

Your Seville is a rather common variety 4. Spend some money and buy a high end 4 (Director model or better) and keep the chassis from the Seville as a parts set. That may be the only way you will find a replacement flyback. You can then keep or sell off various parts from the Seville as you desire.

I just finished restoring a CTC4B chassis that is going into my Cheltenham. The HOT current draw on this properly restored chassis is running a cool 175ma, so this is not an impossible current specification.

I truly feel your pain. It has happened to most of us at one time or another. All is not lost, there is always hope that you may get lucky and find a replacement, however it may take quite some time and more than a little luck. Perseverance is the key. Hang in there and just keep looking. Eventually you may find a parts chassis and if lucky it will have a good flyback. Unfortunately the flyback is the first part to be canabilized. That's why I say you should set your sights on another complete set, preferably a Director or better.

[matt99]

That's one good looking TV though. The other day I was reading an old thread where someone had a flyback failure in a 21CT55 and managed to fix it somehow. Maybe the same procedure (whatever it was) could be used on this CTC4. Of course now I don't remember whose thread that was. It was whoever owns the 21CT55 with the hacked up cabinet. Maybe read through that old thread. Sorry I don't have a link.

[ohohyodafarted]

Also, you could get lucky and find the problem is very close to the outside layers of the HV winding. If it is near the outer diameter, you could unwind a few outer layers till you get to the defect, and just re-coat with wax and use the flyback with a few less turns on the HV winding. You would have a bit less HV at the crt, but it's worth a try if the defect isn't too far in from the outside. You could probably remove 10% of the turns and still have enough HV to operate. I think you would still be able to operate at 20KV. Cross your fingers and hope you find the defect very near the outer edge.

[Penthode]

I have been able over the years to resurrect bad flybacks. You will generally find the insulation has cracked or else the is a carbon track across the insulation.

I would ascertain where the arc is by examining the flyback when briefly plugging in the set. That is if the carbon track is not immediately obvious. You could then remove the flyback and give it a thorough investigation. You most likely can remove the carbon track and then seal it with glyptol or silicon and it will as good as new.

Nothing is lost trying and there is a lot to gain.

[vts1134]

Originally Posted by ohohyodafarted

...the minute you sell your only spare, that is when you will need it to fix one of your sets...

Two ways to think about that mentality. One is I'll hoard everything I can find and never sell anything so that IF I come across something that needs parts I, and I alone, will have the spare parts I need. My island will be full of the fruits of my hoarding, but I will be alone on it. The other way to look at it is if I have a spare part you need and I don't then I sell it to you. Murphy's law dictates that yes I'll need that part minutes after I let it go, but such is life. My island becomes not so full of shiny things, but full of other people and we all benefit. I love that this hobby is full of people who think closer to the latter than the former. Everyone is free to keep and share whatever they feel fit and I'm not advocating antique television socialism, but good for those people that do let (some) precious parts go to others.

[DaveWM]

while not a color set it give the idea of the tripler
this is me messing with a BW tv:

https://www.youtube.com/watch?v=li-kxlpA0mU

this guy has lots of great videos on flybacks:

https://www.youtube.com/watch?v=tVK2ZoiT9uA

Don't give up too fast on the one you have

[Hagstar]

Originally Posted by vts1134

Two ways to think about that mentality. One is I'll hoard everything I can find and never sell anything so that IF I come across something that needs parts I, and I alone, will have the spare parts I need. My island will be full of the fruits of my hoarding, but I will be alone on it. The other way to look at it is if I have a spare part you need and I don't then I sell it to you. Murphy's law dictates that yes I'll need that part minutes after I let it go, but such is life.

Myself I have found spare parts in reserve act as a talisman where you'll never need them Seriously though I have always relied upon the kindness of strangers.....

John H.

[vts1134]

Originally Posted by Hagstar

...I have always relied upon the kindness of strangers.....

John H.

Me too.

[ohohyodafarted]

Originally Posted by vts1134

Two ways to think about that mentality. One is I'll hoard everything I can find and never sell anything so that IF I come across something that needs parts I, and I alone, will have the spare parts I need. My island will be full of the fruits of my hoarding, but I will be alone on it. The other way to look at it is if I have a spare part you need and I don't then I sell it to you. Murphy's law dictates that yes I'll need that part minutes after I let it go, but such is life. My island becomes not so full of shiny things, but full of other people and we all benefit. I love that this hobby is full of people who think closer to the latter than the former. Everyone is free to keep and share whatever they feel fit and I'm not advocating antique television socialism, but good for those people that do let (some) precious parts go to others.

John,

I am sure you have life insurance to care for your new baby in the event of your demise. Having spare parts is a form of insurance against decreased value of an operationally restored collection losing significant value when a rare part goes bad. This is not about hoarding, it's about a type of "insurance" we choose to have in order to feel comfortable. Some collectors are happy to just look at non-operation sets. Others of us want our sets to actually work, (it's about the WOW factor that occurs when non collectors see our collections). But there is very high risk in turning on a set that could go poof at any moment. So we try to have "insurance" against the heartbreak that is sure to come sooner or later. Some parts are easy to get, some are total "unobtanium" and others are just so rare that the only way to get one is to buy an entire set just to get one part you need.

As for me, I am in the middle. I both share, and retain of my parts spares, as most all of us do. Last month alone a Porthole fly and a Moto Yoke. Your implication that there are "hoarders" among us who never share anything, is rather insulting. I don't know anyone in this hobby who is that selfish.

In the end when a collector dies and passes on his estate, there will be an opportunity for everyone to share in the "insurance parts" the deceased collector saved for us. "All things must pass" George Harrison

In the meantime there will be those who have and those who do not. That is just the way life is. We all covet stuff that we don't have, that doesn't mean the people that have those things are bad or selfish, it means they are successful in their endeavor. And when success becomes looked down upon, we end up with Socialism.