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  #16  
Old 08-23-2014, 12:42 AM
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ChrisW6ATV ChrisW6ATV is offline
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Nice, quick work, Tom! That looks good.
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  #17  
Old 08-23-2014, 06:28 AM
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Here here! What a great set and it's starting to come together nicely. I can't wait to see the totally finished product.
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  #18  
Old 08-23-2014, 06:33 AM
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Amazing!!! Great work!!!
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  #19  
Old 08-24-2014, 01:44 AM
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Here are some enhanced scans of the Operating Instructions and the Unpacking Instructions that came with this set. These were severely faded duplicated pages (purple ink), but I think they are just readable after scanning and enhancing.

Also, to follow up on an earlier comment I made: The CRT anode voltage in the Club 20 is measured to be 18 kV, which is basically the same as the Westminster uses for the 20BP4. There was a "Danger - 12,000 Volts" tag inside the set, but this does not accurately reflect the actual voltage on the CRT. Probably a tag more appropriate for the RA-105, which has basically the same chassis, but a different high voltage supply and a 15AP4 CRT.
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  #20  
Old 08-24-2014, 05:20 PM
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Awesome work! Well how about that regarding the dial! A little back lighting and my colors appeared from no where! Cool!
Attached Images
File Type: jpg image.jpg (86.4 KB, 82 views)
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  #21  
Old 08-28-2014, 05:17 PM
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Regarding the colors on the back of the dial. My RA-105B "Sussex" dial had most of the red and green translucent paint rubbed off.

Testors Candy Apple Red And Green translucent clear paint, available in spray cans are a dead nuts match. Mine looks great.
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  #22  
Old 10-12-2014, 12:40 AM
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An update on this set. I've been working on it a bit here and there over the past month, and it's pretty well dialed in now. The cabinet finish was good enough on this one that it only needed a bit of Howard's Restore-A-Finish. A few shots of the set attached.





And a few more you can click on...
Attached Images
File Type: jpg dumont_ra106_cub_20_front_right.jpg (43.3 KB, 327 views)
File Type: jpg dumont_ra106_cub_20_front_closed.jpg (49.3 KB, 24 views)
File Type: jpg dumont_ra106_cub_20_front_open.jpg (47.8 KB, 40 views)
File Type: jpg dumont_ra106_club_20_control_panel.jpg (64.2 KB, 324 views)
File Type: jpg dumont_ra106_club_20_back_closed.jpg (50.5 KB, 44 views)
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  #23  
Old 10-12-2014, 12:43 AM
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Tom Albrecht Tom Albrecht is offline
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The set works very nicely now. Its only shortcoming is that the picture is not as sharply focused on the left side of the screen. I find the focus uniformity is a little better with a brightener on the CRT, so I think the cathode center is a bit worn out. Not sure why this happens more on the left side of the screen, but it certainly is better with the brightener. The center of the screen is very sharp with or without the brightener. I will soon transfer this 20BP4 CRT to my Westminster, and will see if the behavior is the same, which should clarify whether the problem is the set or the CRT.

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  #24  
Old 10-12-2014, 12:51 AM
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Tom Albrecht Tom Albrecht is offline
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Although this set is very rare in its own right (probably only 2 or 3 left in existence), the real draw is the 20BP4 CRT, which I will transfer to my Westminster soon. Then the 19DP4 sub which is the Westminster will find its way into this set.

The 20BP4, with its very low deflection angle, Pyrex envelope, Frankenstein-type anode connection, and highly convex screen is quite a thing to behold:



Here's a closeup of the label:



Although a lot of DuMont stuff is really high quality. This particular CRT doesn't quite fit DuMont's "First with the Finest..." motto. These glass bubbles in the screen are pretty big, and very noticeable when viewing the set:



I'm also curious as to whether this might be a rebuilt CRT. Since the 20BP4 has a Pyrex envelope, most CRT rebuilders would not have been able to rebuild this tube. Maybe it went back to the DuMont factory? The reason I'm curious is the green glass joint visible in the neck of this tube. An earlier (gone to air) 20BP4 I used to have (the one that came with my Westminster) didn't have anything like this. I wonder if this is a soft glass neck joined to a Pyrex funnel? The green glass might be a matching glass to join the two together. Also note in the label picture above, there appears to be a shadow of an old label, along with the new label, both apparently done by the DuMont factory. Did DuMont do their own rebuilds? Or was this one rebuilt in its original production (failed some test when first built, and was then reworked)?

Attached Images
File Type: jpg 20BP4 in front of set.jpg (82.5 KB, 341 views)
File Type: jpg 20BP4 label.jpg (46.9 KB, 339 views)
File Type: jpg glass bubbles in 20BP4 screen.jpg (20.6 KB, 332 views)
File Type: jpg green glass joint on 20BP4 neck.jpg (45.7 KB, 340 views)

Last edited by Tom Albrecht; 10-13-2014 at 11:27 AM.
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  #25  
Old 10-19-2014, 10:52 PM
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Nice work, Tom, and interesting notes about the CRT. That green ring is odd indeed.
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  #26  
Old 10-29-2014, 07:34 PM
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Perhaps the Bar models got the third rate production CRTs since many of the viewers would be too drunk to notice the imperfections, and those sets would not wind up in the living room of some well to do customer's house like the other 20" models.
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  #27  
Old 10-29-2014, 10:19 PM
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Quote:
Originally Posted by Electronic M View Post
Perhaps the Bar models got the third rate production CRTs since many of the viewers would be too drunk to notice the imperfections, and those sets would not wind up in the living room of some well to do customer's house like the other 20" models.
I actually think that's sound reasoning. What bartender in a soiled wifebeater and 5 o'clock shadow is going to care about those tiny spots? A lesser amount of character comparing to his own sordid past.
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  #28  
Old 10-30-2014, 08:18 AM
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dtvmcdonald dtvmcdonald is offline
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Try a Geiger counter on the green glass ring. Its probably a Uranium glass.
My very old (three Germanium transistor) Geiger counter does register,
barely, on the green glass in Pyrex to soda-lime glass seals.
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  #29  
Old 10-30-2014, 10:33 AM
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Tom Albrecht Tom Albrecht is offline
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Very interesting! I don't have a Geiger counter, so I won't be able to check your theory, but it sounds like this type of glass is known for being used to join Pyrex to soda-lime glass. That all makes a lot of sense, and we have probably figured out that this thing was indeed rebuilt with a soft glass neck and replacement gun.

That would seem to indicate that the rebuild was not done when the tube was first made (to correct some mfg flaw), but at some later point. I would guess that if they had rebuilt it when it was made, they probably would have been capable of putting a Pyrex neck on the Pyrex tube. A few years later, when Pyrex tubes were no longer made, a rebuild like this would have made more sense.

With the bad tube that came with my Westminster, I actually tried to get a rebuild like this done. Clinton agreed to rebuild the tube if I could get a soft glass neck joined to the funnel of my Pyrex tube. I got the custom glass piece to join Pyrex and soft glass from an outfit in New Jersey, and got a glassblower here in California to agree to join it, but unfortunately, the glassblower here was not successful, so I abandoned the plan. Seems like it was a good plan, but I didn't have the right glassblower. Anyway, I'm glad to have this 20BP4 now.
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  #30  
Old 10-30-2014, 04:03 PM
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Perhaps some CRT tech was attaching the gun and ran into a jam and used a cross cut from a green bottle that held his soda or beer hehe

SR
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