#46
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Just for the record, what kind of temps are we talking about and what type of oven is this in? I sure hope there aren't people trying this in their typical Tappan oven....
By the way I have found this thread very interesting and have learned much from it. Thank you. |
#47
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CRT Rebuilding equipment
With all of this interest in CRT rebuilding, it begs the question, why doesn't anyone want to experiment?
Twice over the course of the last 15 years, I've been offered CRT rebuilding stations from defunct shops, and I've have never found any one willing to buy and/or pickup the equipment. One offer to me was for a free set-up (Come and get it!), and the other was for about $1,000 or $2,000. I also remember one or more set-ups offered on ebay in the last 5 or 6 years. I always wished I could make the room, and the time, but if I had taken any of these, they'd still be kicking them around in the back of my garage! |
#48
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Experiment on whose CRTs? How many guinea pig tubes would it take to gain "experience" ? And how valuable would that experience be if you finally succeeded in rebuilding one usable tube after dozens of rejects--is that when you'd hang out your shingle? Scary thought.
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tvontheporch.com |
#49
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Doesn't the rebuilding process require some new parts? Where would a person find them? Old P1 or P7 CRTs (non P4) are a dime-a-dozen still and would be good for practice. I suppose a person might take the gun & neck from a NOS 5FP7 and put it on a no-emission 7DP4 and make it worth his while. Could a person mount a set of color guns from a modern-ish Zenith rectangular CRT onto an "aired" 15GP22? Beats me.
I'd give it a shot if anybody wants to offer his "Come n get it" special (and you're not on the far side of the moon). I would think ten ten-dollar 'scope tubes would be a worthwhile hundred-dollar learning experience, to set up shop rebuilding those 500-dollar RCA 621TS tubes. |
#50
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I think the only way that this could be successfully done is for someone to become an apprentice to Scotty at Hawkeye for a few months to learn the art.
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Audiokarma |
#51
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It's built the same way as a glass tube. We actually had less trouble with the metal tubes than the glass ones.
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julian |
#52
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Quote:
Zworykin while working at Westinghouse in 1929 developed and patented the first hard vacuum crt with an electronic lens. This is what he called the "kinescope" and is the basis for all modern crt's. It is said that most experts of the time scoffed that this was impossible, and RCA did not publicly show the kinescope until May of 1932, and then only to RCA licensees. Darryl |
#53
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Quote:
In a gassy tube the negative voltage at the metal cylinder was adjusted for a focussed beam with maximum brightness. When the beam current was lower or low, the focus became poor, and as a result, the point on the screen became darker. In this way, one effect of the gassy tube was an improvement of contrast, but a loss of gradation. The high vacuum tubes generated a more natural b/w picture with an improvement in gray tones and gradation. - Eckhard |
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