"Tune in next week..." That's like forever! At least when you're waiting for something exciting like this.

John

Hello Gentlemen,

While-U-Wait for more news on Bob's/John's 15G, why not read a bit?

I've scanned for you 4 interesting Color TV-related articles from the RCA Lancaster factory magazine:

- Milestones in color picture tube development - H.R.Seelen
- Development of cathodoluminescent phosphors - A.L.Smith
- Gasses & Getters in color picture tubes - Turnbull/Moscony/Month/Hale
- Colorimetry & contrast performance of color picture tubes - Ehemann/Rudy

RCA Lancaster: Main Directory
http://s281.photobucket.com/albums/k...ancaster%2069/

For those in a hurry, the link to the Gasses & Getters article (4 pages):
http://s281.photobucket.com/albums/k...tersinColo.jpg

Best Regards

jhalphen
Paris/France

Interesting Read Jerome, Thank you!

Update: The 15GP22 from Scotty has arrived at my house. :banana: No damage, all appears well. The tube has not been based yet. Bob Galanter will arrive tomorrow, so I am waiting so he does not miss any of the fun!

"one small step for a man ... "
 

MAY GOD SPEED, JOHN FOLSOM.

Regards,
Terry Cheek

That's almost more beautiful than my Lovely lady Friend! Almost!
Great news!! Look forward to the first screen shots!

thanks for the articles, Jerome

I wonder if the carrier realized how many people would be angry if they broke your 15GP22?

Have fun you guys!

John

This tube was under Vacuum so what was the original problem, just weak or dead?

Eric, I think this post from an earlier thread is describing the tube in question:

http://www.videokarma.org/showpost.p...9&postcount=17

Ah, thank you, that was one really dead tube!

Erich H, Just to pick a nit, the 15GP22 just rebuilt was NOT the one Bob described. This tube was one I had which had a bad gun but was still under vacuum. This is the second time this tube has been through the rebuild sequence at Hawkeye. The first attempt failed when the stem cracked towards the end of the evacuation cycle in the oven. The newly redesigned stems we had fabricated seem to have fixed this problem. At least on a sample space of one.

Im excited to see the end result! This is great news and yes, One small step for man, one giant step for mankind indeed!!! "Kid in a candy store"!!!

Essential Expansion
 

Thanks John........Bob's custom jig and EDM (electro-dynamic machining) was truly the breakthru on this ambitious project. I imagine the crt vendor just had to slip his new heater/cathode tube into the hole Bob bored into the original cathode cylinder?? I would be very interested in the total rebuild cost with profit. Scotty quoted me $400 for my 21FBP22 which is a slam-dunk in comparison. Tom

Any plans to video the first start... would be neat to see a dark screen come to life!!!! Just like man walking on the Moon.

:worthless

OK..It's Official...We have Ignition...
 

(posted from John Folsom's computer being tybed by Bob)

I arrived at John's house on Saturday afternoon around 1:30 eastern and after having a brief lunch we started our work.

The first order of business was to mount the base on the 15G and solder the wires. We then proceeded to test the crt with the Beltron. Because the cathodes had not been run through the complete activation protocol the guns tested rather low. So we ran through the cathode activation protocol that had been given to us by Scotty. That took about a half hour and after the protocol had been run we retested the 15G on the Beltron. Blue and green were fairly good but the red was still substandard. So we ran the Beltron "cleaning" protocol and VIOLA the red gun came alive.

We now had very good emission on all guns and as the next few days of operation showed, the emission got even better as we used it more.

With that done we mounted the 15G on a CBS crt truck and pulled a CT100 chassis from one of Johns sets that had been recapped some time ago.

So... the next thing to do was hook the 15G up to the CT100 chassis to do a real world test. The CT100 chassis was giving us a lot of problems. The picture the chassis was supplying was VERY bad. There was evidently something wrong with the front end of this chassis. HOWEVER, before we could get the problems in the front end of the chassis resolved, we developed a HV problem. The flyback was hotter than blazes and arcing and so we spent the next several hours replacing the CT100 flyback.

ONce again we fired up the chassis and now we had good HV and started tweeking the controls to try and get a decent picture. We were still being plagued with poor signal quality, but the crt was lighting up nicely. But the picture quality sucked. We subbed a signal from a test tuner and got a fairly decent picture so we decided that the problem was in the tuner on the ct100. So next we pulled the top section of the ct100 tuner and subbed a different tuner into the set. Still the picture quality was lacking. IN a last ditch attempt to get the chassis running we decided to do a front end IF alignment. Unfortunately that did not help much and we still had a very bad picture on the 15G.

Now two days into the project we are not getting very far so John decided we wasted enough time with the CT100 chassis and made an executive decision to abandon the CT100 chassis as a driving mechansim and go to plan "B". We decided to use John's Westinghouse H-840CK15 chassis as the driver for our tests.

So after making a number of adapter cables and setting everything up, and doing a fair amount of initial tweeking, we now had a pretty decent color and B&W picture on the new 15G.

Murphy's law states that "whatever can go wrong will go wrong" and so of course not long into our tests with the Westy chassis, we heard a big "snap" and we lose the picture on the 15G. After some brief expert diagnosing on the part of JOhn, we came upon the discovery that the 30KV 2000pf doorknob had taken a dump. But never fear, John had a spare and in about 2 more hours and a trip to Ace for some metric screws, we were up and running again.

That brings us to MOnday morning. We now have a Westy chassis that is operating and driving our newly rebuilt 15G. AFter a few hours of purity, convergence and assorted other chassis tweaks we finally had a VERY NICE picture on the new 15G.

Over all we are very pleased with the performance of the tube. We do however, have a small problem with purity. On INitial power up cold start the tube has very good purity. After it warms up, we get a shading of color shift to the green on the right side of the tube. In our opinion the purity issue is rather minor considering the brilliant Technicolor picture we are getting from it.

Future plans are for John and Bob to make another trip to Hawkeye to rebuild two more "under vacuum" duds and attempt to also seal and rebuild a leaker. We are hoping to make the next attempts before the end of the year, or very shortly after the beginning of the new year.

Before we do that, however, we will need to have more gun assemblies rebuilt. Will be proceeding with that as soon as possible

The actual image on the rebuilt crt is far far better than these photos show. We tried over and over to get some screen shots that looked as good as the crt looks in person, but we could not get any shots that looked very good.

So there you have it. The 15G is rebuild-able.

John Folsom and Bob Galanter

WOW what a saga!

BRAVO!!!! :banana::yes::banana::thmbsp::banana:

Good work !!!

jr

Zowie! You guys are having way too much fun.

Phil

woa.. wholly hell. the first successful 15GP rebuild ever. bravo. Oh, btw, IT LIVES!

Rebuilding the 15GP22
 

Quite an accomplishment!

The first rebuild in Modern Times.

Do some celebrating tonight.

Ed

The "end of the yellow brick road." How apropos! Nice color too.

John

Kewl !! A miracle about on the same order of magnitude as the Loaves 'n' Fishies, if you're an old TV nut...(grin)

Fantastic job, and, brilliant color! Great job, guys!!!!! :banana:
Bill Cahill

I can imagine you guys were wanting to pull your hair out while trying to deal with the CT100!

"We're so close... so close... and now we have to deal with chassis issues!!"

You guys get the gold star this week... that's for sure! Those pics are great!

I just got a chance to read up and look at the pictures. Congratulations Bob, John and Scotty on a job not ever done by anyone else in modern times. Truly amazing work guys!

Fantastic! Thanks for all your work on this, and thanks for not giving up.

Shucks folks,I'm speechless!!!

Like breaking the 4-minute mile - now we know it can be done!

Hoorah!

Congratulations on seeing a real payoff from all of your work, Bob and John.

Congratulations
 

Great work guys.
I'm really proud of you and your accomplishment.

Long Live The 15GP22!

Regards,
Terry Cheek

Wow that is just fantastic news! We all knew you guys could do it! :thmbsp:

One question, Was this the same gun that went through the partial rebuild previously when the stem broke? or was this another gun assembly?

I've really enjoyed this sort of "back to the future" thread! Congratulations.

Reece

After more tweaking ......
 

Bob and I have spent some time tweaking the Westinghouse 15" color set driving the rebuilt 15GP22. While there are still some unexplained purity defects, mainly in the reg/green domain, when displaying a color picture these artifacts are less noticeable

We are going to declare victory. :banana:

Bob and I have now move on to playing with the Mitsubishi Trinescope color TV. Bob has given a demo course in can capacitor re-stuffing, and we are just about ready to give the little set a try.

15GP22 Rebirth...
 

John and Bob,

Congratulations on your accomplishment.

It's an honor to know you guys.

Pete

We do not know for sure. We have a number of guns in the Q and we are not certain if this is that same gun or not. Our inclination is that it is not the same gun, because that gun was sent via USPS to the gun rebuilder and it is currently unacounted for.

I've been holding my breath (and tongue) awaiting the test results. Now that they are in...

http://bestanimations.com/Holidays/F...ks-10-june.gif

HOORAY!

Congratulations and much thanks to John and Bob for their success. This project was discussed at the first ETF convention in early 2003, now here we are in late 2009. That's determination! :thmbsp:

Where and how do we line up to join the rebuild parade?

Step 1: Send your check to Bob & John. Don't bother to fill in the amount, we will do that later!