15gp22
 

Since Eric opened a can of worms on the 15gp22..LOL..I have a dud 15gp22 in the basement,i also sold my ct-100 last year to a guy in france.(working).
so i called this place that says they can rebuild the 15gp22 and others.
A lady who answered the phone took my name and number down and are suppose to call back,i will let you all know what is what.!:)
terry

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15gp22
 

well its been several hrs since i called them.
no return call..so i called them a 2nd time,this time a guy answered and didnt speak very good english at all,as a matter a fact i had to ask him to repeat what he said..finally he said.. "someone will call you back about 5:00-5:30 pm". click
maybe they dreamed they could rebuild the 15GP22?
kinda like i dreamt last night my Male cat had kittens..:)
terry

Questions for the 15GP22 Rebuilder
 

If you get a hold of someone (guess you've already figured out not to hold your breath...) and you get a price I think it might be a good idea to find out just what these guys are doing. Why not ask or email them for details. After all, you got a rare tube. Here're a few questions I would ask:

1) Physical damage to the tube face plate - if so then it may not be repairable. Any scratches or chips may cause tube to implode of crack during baking. Then again, it may not. Just all depends on the damage and where. For a sizeable chip of glass out of a corner of the tube may be courting disaster!

2) Is the tube at air/low vacuum/condition of the getter (silver or white)?
If tube is still under vacuum and getter is silvered then:
What is their inspection process?
If tube is at air do they break the seal cut off the old gun assembly?
and then connect the open funnel stub to a vacuum chamber to do a
slow outgas pre-bake at 150 deg C to drive off water vapor?
It's a hell of a lot easier to pull water out of a 2" stub than a 1/4"
evacuation nipple to pressures of at least 10-6 torr!

3) What's their experience rebuilding the 15GP22? References?
4) What's their rebuilding process? In house or RCA?
5) When they break the seal to start the process do they do it vacuum?
6) Once the seal is broken do they back fill the tube with dry N2 gas?
It may be necessary to physically handle the 15GP22 by hand unless
the rebuild chamber can accommodate the tube easily and be kept
under vacuum at all times.
7) How do they alignment of the gun with the phosphor plate?
8) Do they know which gun goes up?
9) Where did they get their replacement gun assembly?
10) Are they capable of rebuilding the electron gun with new filaments?
11) How do they prepare the tube?
12) How do they prepare the replacement gun?
13) What maximum temp do the bake the tube?
There is no need to exceed 300 degC. Maximum tip off temperature used according to RCA research papers described limiting the original manufacturing process to this temp for the 15G. I would suggest not exceeding 200 DegC but, instead, allowing the tube to bake for a day then gradually reduce to room temperature over 7 days.
14) Are they doing anything special to prevent thermal shock to the phosphor plate?
15) Do they thermally cycle the tube? If so, periods and ramp times?
16) Do they do local annealing of the new glass seal on the gun assembly?
17) What is the maximum tip off temperature during baking?
18) Do they helium leak test the face plate to cone (funnel) seal?
A helium leak test of the feed throughs at the gun base after a replacement gun it critical to make sure the replacement seals are good.
19) Are they able to place a 20KV charge to stress test the tube?
The ability to stress test while actively pumping the tube before sealing allows the rebuilder to further outgas the tube. Especially since these tube have been sitting around for 50 years.
20) How long do they evacuate the tube before sealing?

I suspect that attempts to build these tubes in the past have failed not because of the gun replacement parts (...don't rule anything out though!) but because of suspect improper evacuation, outgassing and stress testing before sealing the tube before finally firing the getter. In my mind, there's no reason why a 15GP22 can't be easily rebuilt. However, if the tube rebuilder thinks they can do a regular 'slap and dash' job like on a modern all glass CRT then it ain't going to be so! Success takes time, exceptional vacuum technique and extreme patience, especially with the rebuilder taking their time not baking the tube to the point where seals and/or phosphor plate are damaged.

Anyways, give it shot. Let's see what they say.

Tom

15gp22
 

well its obvious they are not going to return calls as they said..
why would a company mislead about something as this?.i bet they dont really even rebuild the antique tubes they say they can do..maybe it was suppose to say "ANTIQUE TUBES NOT REBUILDABLE" ...but they coulda told me on the phone or called back..maybe ill stick my dud 15GP22 that i have no chassis for into the kitchen oven and see what will happen..:)

I don't think they rebuild any tubes. Notice all the other activities they supposedly are involved in.

15gp22
 

this is a cut and paste of what they say on their website...below
************************************************** *****
Below is a listing of the types of tubes we rebuild at WMicronics.

Rebuilt Color Picture Tubes
A66EAF51X01 A66EAK00X01 A66EAK22X21 A66EAK51X01
A66EAK71X11 A66EAS01X01 A66ECF25X05 A66JMZ30X01
A66EAK071X11 A66EAK252X11 A66EAK552X11 A66EAS00X01
A66EAS13X01 A66ECF00X01 A66ECF10X05 A66ECF25X01
A66ECF50X12 A66ECF61X71 A66ECY13X01 A66EHJ43X01
A66PNT16X A66ACT07X A68AGD01X A68EAU25X02
A68EGD032X322 A68ESF002X11 A68ESF002X111 A68ESF002X43
A68KVL74X01 A68KZN696X99 A68EAU28X01 A68ESF002X143
A68JUA125X A68KKN96X01

Screen diagonal 28" and 29" with Full square or Full and Flat.


Rebuilt Black & White Picture Tubes
3KP4 5BP4 7DP4 15GP22
21AXP22 21CYP22

These antique tubes are rebuildable,and can be rephospored. Gassy tubes can be rebuilt. Contact us for a quote.

[QUOTE=On the subject of phosphors, I've had the unpleasant experience of discovering the non-aluminized black & white tube phosphor the easiest to damage if you suddenly break the seal off nipple at the base of the gun. You can blow away a circular patch of phosphor several inches in diameter off the face plate.>>>

Probably is a way to do it by putting some flexible filter or device over the nipple so when it is broken, the air has to go thru the filter or something like that to slow down the de-vacuuming of the tube (?) Maybe just a little rubber hose slipped over the nipple with a filter or pinhole plugged into the other end of the hose.

Squeege real hard ...then squeeze some more!
 

[QUOTE=frenchy][QUOTE=On the subject of phosphors, I've had the unpleasant experience of discovering the non-aluminized black & white tube phosphor the easiest to damage if you suddenly break the seal off nipple at the base of the gun. You can blow away a circular patch of phosphor several inches in diameter off the face plate.>>>

Probably is a way to do it by putting some flexible filter or device over the nipple so when it is broken, the air has to go thru the filter or something like that to slow down the de-vacuuming of the tube (?) Maybe just a little rubber hose slipped over the nipple with a filter or pinhole plugged into the other end of the hose.[/QUOTE]

Frenchy, the early non-aluminized tubes were coated with phosphor that were typically atomized or gravimetrically settled onto the face plate via a liquid alcohol suspension. Baking the tube during evacuation removed the volitials and leaves the phoshpor on the face plate. The only practical way to bring these tubes up to air without disturbing the phosphor is using a very slow leak. Specialty equipment used during rebuilding usually places the entire tube in a vacuum before the vacuum in the tube is breached (usually the neck is cut off to replace the gun assembly). Using a filter on the nipple I doubt would work as it takes only the smallest amount of air rushing in at about 300 miles per hour to disturb the phosphor.

Remember there's about 1,400 lbs/ square inch pushing down on a CRT from the outside world. Ya gotta grab onto ur hose and squeeze it real tight to slow'r down!

Finally, an e-mail reply
 

[QUOTE=Steve D.]I e-mailed these folks after reading this thread. No reply yet, but the disconnected phone probably tells the story.

I received this e-mail reply this morning:


Steve:
I am on the road this week and I will respond around the middle of next week,when I return.

Regards
Ian B.M.Charles CET
Western Micronics CDN.International
RECYCLE! for a cleaner Environment
http://www.wmicronics.com
A caribe company
110 - 112 East North First Street
Seneca SC 29678
1-864-985-1556


Steve D.

Western Micronics
 

[QUOTE=Steve D.]
Steve, I also got a similar reply today from Ian Charles. He omits mentioning he'll return! Ha...

-------------------------------------------------------------------------

From: Ian Charles [mailto:[email protected]]
Sent: Tuesday, December 06, 2005 8:21 AM
To: Tom Ryan
Subject: Rebuilding Antique Tubes


Tom:
At present I am on the road and I will respond around the middle of next week.



Ian B.M.Charles CET
Western Micronics CDN.International
RECYCLE! for a cleaner Environment
http://www.wmicronics.com
A caribe company
110 - 112 East North First Street
Seneca SC 29678
1-864-985-1556

--------------------------------------------------------------------------

So, anyone know what's the reference to a caribe company mean? I found the following on yahoo, not sure if this is the one:

Company Profile
Updated: 05-JUL-05


Signal Caribe Inc.

Private Subsidiary, Headquarters Location
St. Just Rd., St. Just PR 00978, United States
(787) 761-2620,
Line of Business: Manufacturing: Manufacture of electronic components.

Add me to the list of those that have a spare 15G dud....

this is why rebuilders have to rephosphor mono crt's.
i change out a few of these a week when rebuilding these control heads.

Now THATS burn-in!

If the brightness had been turned any higher it would have been a burn THRU!
: )