#76
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You have a DuMont RA-101-1A:
http://www.myvintagetv.com/dumont_101a.htm A better forum to find out stuff about old TVs is: http://www.videokarma.org/forumdisplay.php?f=19 |
#77
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Steve-
I am happy to read about all the progress that you and others have made with the CRT project. One thought I had, now that I have read both the entire Web page as well as the discussion here: I noted that the heating element is from a convection oven. Would it be feasible to obtain and use the element(s) from a self-cleaning electric oven? During the self-cleaning process, those ovens go up to maybe 800 degrees, if I remember right. Such an element would need 220V wiring.
__________________
Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." |
#78
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Quote:
do say not to touch or open it, temperatures will reach 750 - 800 degrees.... I have never used the self cleaning option.... .
__________________
Yes you can call me "Squirrel boy" |
#79
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There is nothing unique about the heating element in self cleaning ovens. The one I'm using with the fan is from such an oven. Mine is 8400 watts at 240v.
The reason I am having more difficulty reaching 700 degrees relates to the size of the oven (4 times the volume of a typical oven) and air leakage. I am in the process of using an automotive silicon sealer on all the interior joints of the oven. If this doesn't bring it up to the desired temperature I will add an additional heating element - like a stovetop element. I can add about 1400 watts and still power it from my 40 amp breaker. |
#80
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One thought on 7JP4 rebuilding. There were many essentially identical scope tubes made so if a gun gets shattered in transport or something similar, robbing the parts from a less sought after scope tube may be a solution. It could also potentially be worth wile to rephosphor otherwise identical scope tube types to make new 7JP4s.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
Audiokarma |
#81
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Unfortunately, just robbing the gun from a 7JP1 scope tube won't work.
Once the tube is let down to air, the cathode needs to be replaced, because the active oxides become contaminated. If you are going to go through all that trouble, you might as well just rebuild the 7JP4 guns themselves... |
#82
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OK, that is good to hear. I hope things go well with the insulation and sealing efforts.
__________________
Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." |
#83
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Quote:
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
#84
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I'm hoping someday they can make a bunch of 3KP4s out of all the 3KP1s I've been saving.
. |
#85
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That has the potential of being even more lucrative than doing the same with the 7" CRTs. There would be a lot of happy Pilot TV owners...
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
Audiokarma |
#86
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Here is a video produced by Bob Galanter that shows the rebuilding process used at Hawkeye:
http://antiquetvguy.com/Web%20Pages/...ie%20Page.html |
#87
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The oven is now working perfectly. Take a look at our latest progress report:
http://www.earlytelevision.org/crt_project.html |
#88
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The RACS equipment is halfway across the Atlantic. It should be in Norfolk on the 26th, then in Hilliard by about December 1.
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#89
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Thanks for the update!
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#90
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It's an early Christmas miracle .
__________________
John |
Audiokarma |
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