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  #61  
Old 03-04-2009, 10:20 PM
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bgadow bgadow is offline
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The last line is important! You could have lots of creative fun with all that is at your disposal. Next thing we know, you'll have built your own custom color crt!
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  #62  
Old 03-05-2009, 11:57 AM
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Hi,
I don't really want to change the subjet after all the interesting technical information on custom color crt's.

I contacted vdc the other day and recieved a reply that they no longer regun 21 inch color crt's like the 21fjp22. I was looking at all options that are still available for rebuilding. Has anybody else contacted them abount round color crt repair, since Steve did in the earlier post.

Mike
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  #63  
Old 03-05-2009, 12:27 PM
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I think I'm the one that drifted off topic. I should have started another thread. Yours is more pertinent to the original thread.

John

Quote:
Originally Posted by mikeh View Post
Hi,
I don't really want to change the subjet after all the interesting technical information on custom color crt's.

I contacted vdc the other day and recieved a reply that they no longer regun 21 inch color crt's like the 21fjp22. I was looking at all options that are still available for rebuilding. Has anybody else contacted them abount round color crt repair, since Steve did in the earlier post.

Mike
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  #64  
Old 03-05-2009, 04:54 PM
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old_tv_nut old_tv_nut is offline
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Quote:
Originally Posted by mikeh View Post
Hi,
I don't really want to change the subjet after all the interesting technical information on custom color crt's.

I contacted vdc the other day and recieved a reply that they no longer regun 21 inch color crt's like the 21fjp22. I was looking at all options that are still available for rebuilding. Has anybody else contacted them abount round color crt repair, since Steve did in the earlier post.

Mike
Have no info on vdc, but wondering why you don't contact Scotty if vdc says they no longer do it.
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  #65  
Old 03-05-2009, 05:41 PM
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Good point, I was just checking out options, $450 to $500 is big money to me.
To preserve some of these marvels of technology from the past for future use it, is now time to just pay up and get it done while it is still possible. I will contact Hawkeye and pay up.

Mike
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  #66  
Old 03-05-2009, 06:14 PM
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RE: 15GP22 issues.

I am working with John folsom on the 15Gp22 rebuild project.

1. There should be no issues with the viability of the phosphors regardless of whether or not the crt is under vacuum. So long as the tube has been sealed, (IE; the neck is not broken off) the phosphors should be usable.

2. Someone stated that electron guns exposed to air instantly get destroyed. That is true only for electron guns that have been activated with the RF bomber. Guns that have not had the cathodes activated are not subject to the instant destruction from air.

3. John and I have done a very through analysis of the leak issue on the
15GP22. It is our belief that the leakers have gone to air not from the glass to metal seal, but from 2 metal to metal joints that exist in the manufacture of the ultor ring. And I am NOT speaking of the arc welded joint that holds the front and rear halves of the crt together. Although frit is used in the sealing of glass to metal, and glass to glass, frit must be matched very closely to the expansion coefficients of the glass and metal or the frit will not hold. ON our project we have found an alternative material to conventional frit, that is used to seal fiber obtic glass threads into connectors that must hold a vacuum. This material will be used in the not to distant future when we attempt to do another rebuild of the 15GP22. We are currently working on some issues that need to be resolved before the next attmpt takes place. We will keep this community informed if and when we have some successes to report.
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  #67  
Old 03-05-2009, 08:49 PM
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It sounds like you guys are making some real progress. It's great that you're so dedicated to the project.

If you, or anyone, has a 15GP22 that has gone up to air and isn't otherwise rebuildable I think I could arrange to helium leak test it and determine exactly where the leaks are. I wouldn't be anxious to risk a CRT, that could be rebuilt, by having it shipped.

By any chance is the sealing material that you're referring to F113? A water thin epoxy used for bonding fibre optics into connectors? If it is F113 or a similar epoxy, I do use it for forming vacuum tight connections when I have to fabricate my own, but these are on actively pumped devices.

I don't know that I would recommend it for a permanently sealed vacuum because of its outgassing properties. On the other hand, the exposed area must be extremely small since you're repairing a leak, so it might still outlast the normal life of the CRT.

John
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  #68  
Old 03-05-2009, 10:05 PM
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Consider doing that project soon and giving some money for his efforts at Hawkeye. Scotty said it's been slow lately, Just wanted to give everyone a heads up and started this thread. I need to follow up and see if he has the tech info to do a rebuild project of mine.

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  #69  
Old 03-06-2009, 07:46 PM
WISCOJIM WISCOJIM is offline
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Quote:
Originally Posted by mikeh View Post
Hi,
I don't really want to change the subjet after all the interesting technical information on custom color crt's.

I contacted vdc the other day and recieved a reply that they no longer regun 21 inch color crt's like the 21fjp22. I was looking at all options that are still available for rebuilding. Has anybody else contacted them abount round color crt repair, since Steve did in the earlier post.

Mike
Who did you speak to? I was in contact with Erv from VDC less than a month ago about these. Here is his reply to me dated February 10, 2009:

"Jim:

Received your request for CRT types 21FBP22 and 21FJP22A.

At this time we have no stock of either type. It is possible to rebuild these if good duds are made available. Cost of rebuilding would be $250.00, excluding freight.

Thanks,

Erv Kuczogi
Video Display Corporation
White Mills, PA 18473
Phone: 570-253-3910
Fax: 570-253-3912
[email protected]"
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  #70  
Old 03-06-2009, 10:27 PM
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mikeh mikeh is offline
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WISCOJIM

Thanks for your information. This is the same person I corresponded with via email, three days ago and Erv replied that they no longer rubuild these tubes.
I will contact them by phone next week and ask them about rebuilding, there may have been a miscommunication on my part. The cost of $250 plus freight makes it alot more afordable for me.

Mike
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  #71  
Old 03-07-2009, 08:45 AM
WISCOJIM WISCOJIM is offline
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Quote:
Originally Posted by mikeh View Post
WISCOJIM

Thanks for your information. This is the same person I corresponded with via email, three days ago and Erv replied that they no longer rubuild these tubes.
I will contact them by phone next week and ask them about rebuilding, there may have been a miscommunication on my part. The cost of $250 plus freight makes it alot more afordable for me.

Mike
Let's all hope you get good news back. Either way, be sure to let us know.
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  #72  
Old 03-10-2009, 12:28 PM
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mikeh mikeh is offline
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I talked to Erv at VDC today on the phone and was informed they no longer rebuild the round color crt's. So I now is the time to get off the fence if you need a tube rebuilt.

Mike
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  #73  
Old 03-17-2009, 10:09 PM
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Scotty just rebuilt a pair of 12LP4A CRTs for me. They test great! He does really nice work.

It'll be a bit before I can put one into a set, but I'm sure they'll perform well.

John
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  #74  
Old 03-20-2009, 06:07 PM
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jhalphen jhalphen is offline
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Good day, Gentlemen,

Follow up on the RACS rebuild of a Telefunken RFB-VI-1 pre-war CRT.

This tube was rebuilt for a collector friend of Eckhard residing in Germany.

Here are some screen shots of the CRT reinstalled in the original TV chassis sent by RACS.

On Feb 23rd of this same thread, pictures were shown of the rebuilt CRT ready to leave the factory. These are proof-of-the-pudding pictures that the rebuild was entirely successful.

Best Regards

jhalphen
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  #75  
Old 03-20-2009, 07:36 PM
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jeyurkon jeyurkon is offline
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Thanks for the update. That's pretty nice work. How many transistions in the glass did they need to handle the pyrex?

Also, what is the "bring your dead CRT to the ETF for rebuild project?" Is this for a specific CRT type or any one that can't be dealt with in the US?

John
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