This is Colin Woods' set I believe, the one I had a tentative deal for and had to back out of due to major logistical issues on my end.

The current price is a steal, check it out:
http://www.ebay.com/itm/282453534738

Yes, that's his. I saw it Sunday when I picked up some other items from him. There will be logistical problems on his end as well. Damn stairs!

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My logistical issues were a wee bit bigger: how do I get it to Oldenburg without having to sell a kidney? It's just so big. At least the Motorola 21CT2M is about the size of a tabletop color set...

It's a nice set, it makes me wish I could move back stateside sooner. :tears:

$1825. Not a great price for Mr. Wood, but not terrible considering how soft the market is.

Man, I just paid more for my 21CT55...Then again I rather have a set with a good 21AXP than a set with a bad 15GP.

I went to a tick over $1500....I admit I bid half heartedly because I figured it would sell for a lot more than it did.....

I put down a token bid for $1800. I'd have just given the cash to my half-brother Mike or my brother-in-law Steve and then paid one of them to pick it up. I'm sort of glad someone sniped me at the last minute.

It was won by a friend of mine. I will let him reveal his name is if he choses to do so.

If it's who I think it is, it couldn't be in better hands.

I spent Saturday 1/6/18 with the new owner of this set. He has acquired a good 15GP22 from a kind collector who was willing to part with one of his coveted good spares. I will not mention his name but this generous collector has our eternal gratitude.

The new owner of the set has completed a complete recap of the set, including re-stuffing all the cans.

Upon initial power up the set had a raster but within a minute or two the raster disappeared.

I am sure all of you know that horrible sinking feeling when your HV goes down. The first thing we all think of is "oh no I hope the flyback has not taken a dump" and in the case of a 15CL100 this would be a catastrophic event, because there are no replacement flybacks available for this set. It used one specific to this set.

So Saturday was spent running down the reason for no HV. Although visually the flyback looked very nice, that is never any guarantee that it's good. It ohm'd out nicely so that was an encouraging sign.

Scoping the waveforms in the horizontal oscillator section was encouraging and showed that we had the correct waveform at the grid of the 6CD6 pair.

We replaced the pair of 6CD6 HOT tubes because they tested marginal and the new pair gave us more of a corona on the plate caps but still not anything to brag about.

The set uses a voltage trippler design similar to the CT100 and 21CT55 but has some odd ball rectifiers, 2V2 and a strange shunt regulator made by GE just for this set. All of these had been replaced with NOS tubes. After some considerable farting around which wasn't getting us anywhere, we decided to start disabling the rectifiers in the trippler circuit. We pulled the 2nd and 3rd stages of the trippler and VIOLA we had about 12KV, with sparks flying all around. Then we enabled the 2nd stage again and it popped up to about 18Kv. But when we enabled the 3 stage, it dragged us back down to nothing. Our conclusion was that the 2000PF 30KV doorknob was leaking. Often a bad doorknob will get rather warm (a sure sign that the DN is bad) but this one was not getting warm at all.

I just happened to have a couple replacements at home in my inventory from when I restored my CT55 (which also had a bad one of these 2000pf 30KV doorknobs.) I usually buy estras of strange parts like this to have on the shelf, because you always have to special order them. Something I learned from my dear friend John Folsom. John's motto is "it's all about the spares" A good motto to live by if you are serious about this hobby.

The replacement doorknob is metric threaded and of course the old GE parts that screw into the DN were Inch thread. So I made some mods to the old GE hardware so that the hardware could be adapted to the new metric threaded DN.

When the set was fired up we got a nice 25KV. The shunt regulator ckt is not working so we still need to address that issue.

The plastic hub on the fine tuning knob was completely broken off of the knob that came with the set. Upon digging through my extensive knob collection, I was able to find an exact replacement that needed some minor fixing. I machined a copper sleeve to place around the plastic hub of the knob and cemented it in place with JB Weld. To make sure that the JB Weld did not ooze into the hole that the shaft goes into, we coated the brass knob shaft with a thin film of silicone grease and inserted the knob onto the shaft. When the JB Weld was cured the silicone grease allowed the knob to slide off of the shaft very easily.

So, progress is being made and here are some photos showing that it is producing color at this very early stage. It still needs work but we are confident that the remaining issues can be addressed as time passes.

The last photo is the GE (on the right) next to the Stromberg Carlson K1 that came from Ed Reitan's collection, for comparison. The photos do not do justice. They look far better in person.

EDIT: Suggesting that this thread might be more appropriate if moved to Early Color Sets

Edit: Photo added

Wow, that's great to see! Looking very well on it's way, nice looking set, and I believe it's the first GE, 15GP22 set, that I have ever seen working in any fashion, I'm not sure I have seen one at all, except in a picture! Fingers "crossed" for continued success on this restoration, and looking forward to more pic's someday.

Looks like a great start. Lots of I and not much if any Q, by appearances. Did this set use I/Q demods like the RCA?

Illustrates the unmentioned reasons NTSC chose the I/Q axes other than the always mentioned one of higher eyeball color resolution on I. Decent people-pics can be obtained with I only. Q axis colors (green and purple) are instantly recognizable as wrong.

Very nice!

1954 newspaper article for the GE 15CL100 color receiver courtesy ETF site:

I would be interested to hear your thoughts about GE making the Hue/Tint control a rear panel screwdriver adjust control. Is the tint stable enough that you don't need to adjust it often? Is the crystal ringing oscillator circuit that stable?

I would be interested to hear your thoughts about GE making the Hue/Tint control a rear panel screwdriver adjust control. Is the tint stable enough that you don't need to adjust it often? Is the crystal ringing oscillator circuit that stable?

The PortaColor has the same type circuit.
The only GE that didn't use it was a IIRC the CA model, RCA semi-clone. If that the one I'm thinking about, the original GE service manual shows the color board as RCA design, including their artwork.
The 1957 GE color set, IIRC 21CL500 with the "L" shaped chassis and three 5U4's had a compression trimmer tint control as part of the front operating controls. That one also used the Victoreen HV regulator. :scratch2:

Yes, that's his. I saw it Sunday when I picked up some other items from him. There will be logistical problems on his end as well. Damn stairs!

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That was fun getting the CTC5 out, I bought from him.
I saw the GE then. That cabinet seems very large compared to the other 15" models.
Ask Bob G. if he remembers getting John Folsom's Admiral out of that upper flat in Sheboygan. That was fun too! :D

GE wasnt done with tint control hijinks. Most of there sets
the tint works the opposite of all other sets. They also reversed
the brite & contrast functions on a few. The PC II & that dog
16" set IIRC.
And to rub it in my GE range has the UP arrow on the left & the DOWN
arrow on the right. Go figure........

73 Zeno:smoke:
LFOD !

That was fun getting the CTC5 out, I bought from him.
I saw the GE then. That cabinet seems very large compared to the other 15" models.
Ask Bob G. if he remembers getting John Folsom's Admiral out of that upper flat in Sheboygan. That was fun too! :D

Yes I remember removing that Admiral 15" set. It was in a 2nd floor room of a hoarder's house. The winding stairwell path to the 2nd floor was only wide enough to walk one foot in front of the other. First floor of the house was so packed that the owner had to crawl over a pile of stuff in the doorway to the bedroom to get to the bed. It took us several of hours to clear the 2nd floor hallway and the winding stairwell to the 1st floor. But well worth the effort because the set had a good 15G and it is an ultra rare set. The Admiral has a very unique cabinet design in which the front swings up and rearward to access the chassis for service and adjustments. VERY COOL!! Admiral did a great job designing that set. Wish I had one.

Here's a photo of the ADmiral sitting in my van after we exhumed it from the hoard house.

I would be interested to hear your thoughts about GE making the Hue/Tint control a rear panel screwdriver adjust control. Is the tint stable enough that you don't need to adjust it often? Is the crystal ringing oscillator circuit that stable?

This has been discussed elsewhere on VK, but the summary is that either PLL or ringing circuits can be designed to do an equivalent job. The GE circuits do not show any noticeable deficit in performance.

The practical reasons why the hue control should have been on the front are variations in burst phase from the broadcaster and the fact that people with normal color discrimination can have a difference in sensitivity to the red and green NTSC primaries (up to +/- 20% worst case according to an early RCA paper).

Yes I remember removing that Admiral 15" set. It was in a 2nd floor room of a hoarder's house. The winding stairwell path to the 2nd floor was only wide enough to walk one foot in front of the other. First floor of the house was so packed that the owner had to crawl over a pile of stuff in the doorway to the bedroom to get to the bed. It took us several of hours to clear the 2nd floor hallway and the winding stairwell to the 1st floor. But well worth the effort because the set had a good 15G and it is an ultra rare set. The Admiral has a very unique cabinet design in which the front swings up and rearward to access the chassis for service and adjustments. VERY COOL!! Admiral did a great job designing that set. Wish I had one.

Here's a photo of the ADmiral sitting in my van after we exhumed it from the hoard house.

Exhumed it, that's funny.:D
At least, we didn't have to call the Medical Examiner. Not much changed in that place, since then.

GE also sold some early 60s color sets, using RCA chassis, the CW and CX. The CW was similar to the CTC11, and the CX was fairly close to the CTC12. I trained on one of those in the early 1970s.