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#16
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Regarding the proposed tube complement for a 9kV RF supply, a pre-war tube complement such as 6N7 (or 6SN7), 6L6G, and 8016 (early Industrial precursor of 1B3) could be used. I believe American engineers may have developed RF oscillator supplies pre-war and either developed the flyback method as part of radar development during the war, or learned the technique from others.
I would need to do some research to determine whether a 10" round electrostatic tube with post-deflection acceleration was part of any manufacturer's product line. Some years ago, I had a chance to pick up a Dumont oscilloscope complete with mobile rack. Although offered for free, I was unable to get anyone to transport the thing 40 miles to my home (I was about 19 at the time, no car, living with parents). That was an interesting scope, perhaps a 10 MHz bandwidth. Its claim to fame, however, was its MASSIVE rectangular screen of about 17" diagonal. Also it was a two-piece device. The scope itself mounted in the sloped top of the rack and its power supply was a separate unit occupying the bottom few rack spaces underneath. About the same time, I did manage to pick up an old USN surplus Dumont scope (date printed inside was 7/1947 IIRC) with an interesting "heads-up" display that was covered by a hinged lid when not in use. That one, I later sold to a collector to raise enough for a down-payment on an engagement ring. This was perhaps ten years prior to my meeting Jan. Incidentally, Jan was the first of the many ladies I had met to ever understand my vintage electronics fascination enough to actually learn to share in it. |
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#17
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Quote:
http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3086643531 I have the Sams on a Belmont 22A21, 22AX21, 22AX22, those chassis use a 7JP4 or a 10HP4 with little or no change to the chassis. They interchange? Will try 10HP4 on chassis from ebay. I also have a 2 section Sentinel chassis that uses a 7JP4 that might be used. Last edited by prewtv; 04-06-2004 at 08:26 AM. |
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#18
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I think the7GP4 and 7JP4 have the same pin connections. You can't damage your tube by trying it, since they use the same filament voltage.
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#19
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I finally found the magazine cover photo that started all of this.
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#20
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Quote:
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| Audiokarma |
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#21
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Would you sell the mag or copy of pages on TV? Thanks for post. Last edited by prewtv; 04-06-2004 at 08:41 AM. |
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#22
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The cover photo was emailed to me some time ago. I don't have the magazine. I'll search the home computer tonight and see if the mail is still there and find out more.
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#23
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Quote:
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#24
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Quote:
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#25
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A note to all the folks trying to figure out the access to the crt and some other details on this photo. This photo, lifted off of my web site by prewtv without my permission, was dramatically damaged in a flood 11 years ago. I spent the better part of a week part time, easily 3 mandays, on the Macintosh rebuilding the lost sections of the image. Almost 30% of the image was lost, including all details of the rear of the crt housing as well as the mount of the housing to the top of the cabinet. All of the details now on this photo are my best guess, and not necessarily correct. I did have the additional advantage that I have a photo of the set, in B&W, from the magazine article, that shows a smaller but relatively undamaged shot from which I gleened some information. This photo shows the set with a test pattern, which can of course can be faked.
About two years ago I drew up drawings for the replication of this set, including mag deflection crt access, as scaled to fit a 10" crt. It will be a while before I get to this project so good luck and best wishes to those who try! This photo is why I am in the TV collecting hobby, and I saved the magazine it is enlarged from from the trash several times when parents wanted to house clean. Just wish I could have saved it from the '93 flood! Marlin |
| Audiokarma |
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#26
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Found place with AMERICAN HOME mags ask about buying this special edition. All other uses of your pic will end in about a week. Again sorry. |
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#27
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Dave, I emailed that photo to you a long time ago.
prewtv, thanks, and to show all that their are no hard feelings here is a post of the original full size enlargement before I restored it. Please note that you can just barely see a line at the top rear of the crt housing that MIGHT be service access. Or a way to change the bulb if it was a fake. If I can get the badly damaged mag apart I will post a picture of the tv with a test pattern displayed. |
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#28
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OK TV folks, here is the entire spread of the article. Sorry about the large file size. Note that the same photo as is on the cover is reproduced, somewhat smaller, in the article.
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#29
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...and here is the close up of the B&W shot:
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#30
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Quote:
I repair electronics for cars at Delphi. So when it comes to wood I am crude. Under the table top I am using a pre made plywood cylinder 27.5 tall and 24 DIA, 7/16 thick. It has veneer on the out side. Need ideas on how to attach to top, legs chassis,ect? Could you send me any ideas? |
| Audiokarma |
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