15GP22.... Good Evening Mr. and Mrs. America, and All the Ships at Sea . . FLASH!!!!
 

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I just got a call from Scotty...........


THE 15GP22 REBUILD IS A SUCCESS!!!


Scotty was just as anxious to see of we had a success as all the rest of us. He got there at 5AM and pulled the tube out of the oven. He did a spark test on the tube with his Tesla coil and she is still under vacuum.

Scotty had other plans for the weekend and so will flash the getters and activate the cathodes on Monday. I will post more about how the guns test on Monday, but Scotty says the gun assembly looks VERY good. "Looks just like a new gun should"

I see no reason that we should have less than excellent news when the guns are tested for emmission after cathode activation.

So it looks like history was made today. I guess all collectors everywhere will have to mark October 24 2009 as a national holiday.

John and I would like to say THANK YOU for all the support and encouragement that that we have received from the collector community over the many years this project has taken. We will continue to update the collector community as things develop.

Bob Galanter and John Folsom
The 15GP22 Project

Yay!!!!!! :banana:

Congrats are in order! John, I can't wait to see the picture on that tube.
Bill Cahill

woohoo!

This is GREAT news!

Wonderful!!!

Bruce

You and John deserve the thanks of the entire collecting community. We really appreciate your massive contribution to the hobby, and to the preservation of history. Our great grandchildren will now be able to see CT-100s and other early color sets working.

You guys are awesome!! Congradulations!!

:beerchug::grnbounce:banana::grnbounce:beerchug:

Congratulations! :thmbsp: Like others, I'm anxiously awaiting the results of the activations on Monday and the first images.

I'm curious about the tesla spark test. What's the procedure?

Let's see, Scotty has other plans this weekend and Iowa is playing Michigan State tonight. Where might he be? :scratch2:

John

Hi John,

The Tesla spark procedure is a hand held HIgh frequency high voltage generator. It has a metal probe about 4 inches long by 1/2" diameter and tapered to apoint.

The probe is placed against the neck of the tube, and if the tube is gassy, the neck of the tube will fluoresce. No fluorescence=good vacuum

Crude, but for crt quality purposes, it is good enough.

This is what it looks like

http://sciencekit.com/high-frequency...l/p/IG0024295/

Bob

That's wonderful! I couldn't believe that Scotty was going to make us wait until Monday. Congratulations on a well-deserved success to all involved in this. I look forward to seeing this tube lighting up the night again with some of that great full-gamut color!

Great News! :banana::yes::banana::thmbsp::banana::yes::banana:

jr

Congratulations mate!!!! :):):) This is bloody awesome news!!! :) With a successful tube rebuilding plant happening, imagine how many CT-100 sets can be restored to working order and other CTC sets and even other brands of early colour sets if the same principle can be used for their picture tubes :). Anyways I'm so glad to know these historic tubes can be rebuilt and I look forward to hearing more success stories with your tube rebuilding plant in the near future! :)

Congratulations and thanks for all you do!!

Congratulations! Always great to hear success stories on in-depth technical projects! Look forward to seeing the CRT in operation.

Bob, John,

Total Congratulations! for success at the end of the Yellow Brick Road, to quote the NG's favorite movie.

Like everyone else, just aching to see pictures!

Kudos! to you guys for the obstination in the face of adversity and persisting with the effort during these long years.

As more tubes are rebuilt, it will be interesting to see if RCA modified the phosphor formulation during the brief lifespan of the 15G.

Best Regards

jhalphen
Paris/France

PS: 02:27AM here (yawn) ;-)

Damn, Jerome, Me Olde Sonne, go to bed !!...(grin)

Thanks, I was curious about how it was used in this case. That makes sense.

I actually have one that I saved from being tossed many years ago. I stuck in a piece of bus bar wire to replace the missing probe.

John

Congrats to all involved! Can't wait to see the first photos.

I remember using one of those to test duds while working for a Sylvania jobber many years ago. Air duds were summarily rejected, sometimes angering the clients!
Kevin

Not to exaggerate, but this has to rank right up with the 1st moon landing, finding the Holy Grail or figuring out who built the pyramids. I've followed this saga since the start...congratulations!!!

Hats off to you!!! You & Scotty deserve royalties on any and all future rebuilds, as far as I can see! I am always impressed when someone takes the notion to do "the impossible", and proves it possible!

The history of trying to do this goes back at least to the mid-1980s, with Ronnie & George at Dunbar in Los Angeles, and later headed by Gary Miller and (un-named collector in Omaha), an attempt by Metrocolor. They came closest in the early 90s, and only failed due to the rusty metal flanges on the duds provided (5 of them provided by the collectors mentioned an myself).

Charles

Congrats Bob, John and Scotty!
 

I've had little interest in the 15GP22 since it had electrostatic convergence and dynamic focus while my 21CT55 had magnetic convergence and static focus. Resteming the 15s seemed to be the last big problem, finding a stem supplier that produces a glass compatible with the original bell glass without cracking, right?

But I still don't know how you obtained the new gun assemblies. Assuming no original guns are available you couldn't use 21in guns since they were magnetic converged. I don't suppose you cutoff the 21's mag convergence pole pieces and attached a simulated electrostatic grid #4 collar to perform the convergence function? Its certainly unrealistic to clone the originals from raw stock. Could you have tediously remove the 3 cathodes with heaters from the original dud and replaced them from new 21in guns.....naw, forget it.

So how did you get perfect replacement gun assemblies for your 15GP22 rebuilds ??? Tom

Tom,

You cut out the 15G gun, send it to have new cathodes and filaments installed, and they then weld it to the new stem. From there the assembly goes to Scotty.

Encouraging news! This may be getting ahead of things, but assuming the process is repeatable, has anyone thought about what price to charge for this rebuild?

Phil Nelson

Great, Great News!
 

Congratulations for making it over another hurdle. Here's hoping the rebuild team makes it to the finish line.

Dear John Folsom,
Please add my name to the guest list for the premier of your rebuilt 15GP22.
Best wishes,

Terry Cheek

This is really exciting news, and I hope the tube installation and operation go as well as the rebuild.

Do you anticipate some quantity of under-vacuum 15GP22s to be rebuilt first before further work is done on leaky ones?

Price has not been determined yet. We still need to work out all of our costs, and determine how the whole thing will work. We will need to colaborate with Scotty and we need to see how Scotty wants to work the arrangement. There are many details athat we have not even thought about yet. It will be a couplemonths before we have the details all worked out and a price set.


ChrisW6ATV, Assuming the gun activation Monday is successful, the tube will be shipped to John Folsom's home in Florida. I will be traveling to Johns house next week and we will install the tube in a set and test it in a real world situation. We will post here in Vk how it turns out.

Some weeks after that we will travel to Hawkeye to rebuild a second under vacuum crt that I own, and we will also experiment with the sealing of a couple crt's that are known leakers to see if we can manage to reseurect the leakey dead.

So we have a couple more months of work at the very least before we will be able to offer the services to all ther rest of the collectors. There is much work yet to be done, but there is now light at the end of the tunnel.

Bob

Congratulations to John, Bob and Scotty!!! This is the best news about color set restoration I've ever heard. It's a tremendous achievement for the state of the art.
Cliff

"Resurrect the Leakey Dead..." Somebody call George Romero-We just came up w/the title for his next movie...See, THIS is what happens when I DON'T have my coffee...(grin)

ahhh that's why I thought of Zombies too this morning. :)

If you are using rebuilt 15GP22 guns, which can't be cheap to rebuild, Don't waste them on tubes that are known leakers. Concentrate on rebuilding tubes that are under vacuum for now, maximize your success rate, improve the process, and worry about the duds that have gone to air later. I'm not sure a tube that has a leaky flange seal can ever be repaired and rebuilt satisfactorily.

Just my thoughts.

I would guess that perhaps most of the 15GP22s that need rebuilding are, in fact leakers. :(

jr

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UPDATE 10/26 5pm

I just spoke to Scotty. The news is somewhat mixed. The good news is that the rebuilding of the guns with new cathodes appears to be very good. Emission is right up there where it should be. Equal to any standard delta gun used in conventional 21" roundie color tubes. A bit slow to warm up at this point but Scotty thinks that it may "wake up" as we use it.

However we did have one slight setback. Un-beknownst to us, the getters were too close to the inside of the neck glass. And when Scotty hit the getters with the RF bomber, the heat of the red hot getters caused bubbling of the neck glass. The tube is holding vacuum, but there is a chance that when the neck heats up from prolonged use, the heating of the glass from the filiments could cause the neck glass to crack and we would lose vacuum. If that should happen, the tube would not implode, it would just go to air and we would have to rebuild it all over again. This problem is easily correctable by adjusting the position of the getter rings on the gun so they are farther away from the inside wall of the neck glass. This will be done starting with the next rebuild.

I have instructed Scotty to put the tube on his test bench and apply 6.3 volts and let it run for several day non-stop to see if the neck glass will hold. There is no point in shipping the tube to John's house only to find out that when we run the tube for a prolonged period, and the neck glass gets good and hot, that it cracks. Scotty said that he has seen this go both ways. Sometimes the bubbles will cause the neck to crack, and sometimes it will hold. Really no way to tell without giving it a good heating.

But at least we know that the guns have what appears to be excellent emmission.

I will post more information as things develop

Bob Galanter and John Folsom
The 15GP22 Project

Amazing! Congratulations guys! I really hope that the bubble in the glass holds. Fingers are crossed, again. :D

Really do hope after all that work it's a good 'un, fingers most definitely crossed! However if trying to root out whether there is a possibility of a failure, wouldn't it be better to cycle the heaters as simply running the tube continuously won't necessarily put the kind of stress on the tube that it'd get in real use.

TTFN,
Jon

Good point. I will speak to Scotty and suggest that he run a cycle of heat up and cool down to stress the glass more like real world condions.

Thank you for the suggestion.

Bob

With the bubbles, could the yoke and convergence components even be installed OK?

The bubbles are very tiny and on the inside of the neck glass. there will be no problem with anything that needs to be mounted on the neck.

Scotty is cycling the tube off and on. 2 hours on and 2 hour off as Duke Nukem suggested. So far so good.

Bob

Tom,
An expansion on what Pete said about having the guns rebuilt: After the gun is removed, Bob Galanter uses an EDM (electro-dynamic machining) tool to mill out the old cathodes from the gun structure with micron precision. Bob built a custom jig to hold the gun assembly which allows the precision EDM machining to be done. Without Bob's expertise, the 15G project whold have come to a halt becausee the company which puts new cathodes and filaments back in ghe gun and mounts the gun on the new stem was no longer willing to attempt the difficult task of removing the old cathodes. I do not think they had access to EDM machining.

Tune in next week for final acceptance test results on the CRT rebuilt at Hawkeye.