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Sherwood S-5500ii Blowing Power Tube (7868)

I had this same exact issue in my Sherwood s5500 III. It was loose sockets. I tightened them and it’s been running great ever since. I did order the NOS sockets Gadget mentioned a couple of months ago. I just haven’t had the urge to replace them yet.
 
More Novar socket info, options and a question.
I have several Sherwood things that use 7868's and my Dyna-Jet 707 tube tester's novar socket is loose with normal 7868 tubes. and too tight for fat pin tubes. I won't get to work on them until the snow flies but just in case, I've been seeking affordable replacement sockets.
I have found a NOS Zenith 873-53 kit on the auction site which contains a brown molded plastic novar socket with holes on 1 5/16" centers. It is screwed to a metal adapter plate with oblong holes on 1 3/4" centers. I've seen a few of these - some were affordable.
Here's a picture of the kit:
Zenith 878-53 kit-2 .jpgZenith 878-53 kit-1.jpg
The socket is the same brand as on the Dyna-Jet tube tester. However Pin 8 is blank - no connection, so it will work for a 7868 tube which has no connection on pin 8, but not for a 6JE6 tube if the G3 connection is needed on pin 8. My Sylvania tubes fit nicely in it.
Otherwise, there is a seller on the bay listing a "9 pin red GLASKYD Novar tube socket B9E fit 7868 6JE6" - says made in USA 1963. I hope I don't need 12 of these.

Anyone know of any successful methods of thinning out the pins on a fat pinned tube, so they'll fit the Novar sockets? (Dip the pins in acid until they fit in the sockets?????)
 
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Build yourself an adapter. Novar plug on one end, Magnoval socket on the other. Admittedly a novar plug isn't exactly a common item but test adapters and socket savers can be had, and its not too nuts to consider taking one of those and modifying it.


if you need a permanent solution and not just something to test tubes with, the answer is to replace the sockets. I did that in my Sherwood S-7000. It takes EH 7868 exclusively now, which in retrospect I'm not entirely fond of the idea but it is what it is at this point.
 
It is kind of unfortunate that the Magnoval tube basing was created and has the same pin locations as Novar. I'm sure that you are aware that if a Magnoval tube is inserted into a Novar tube socket, the socket is permanently ruined. Trying to bend the contacts back usually does not work. A few decades ago, I made that mistake, not knowing there was some kind of problem. I think I was testing a European tube of some kind. That was in a Conar tube tester that I have. I have to twist the tube around etc. to get it to test. One day, I will replace that tube socket. (Hmmm, winter is coming, yard work will cease! Sounds like a plan)
 
If you are going thru the hassle of replacing sockets you might consider just converting to octal sockets and going all 7591 ish. It’s easier to find better oxtails.
 
Dadbar said:
If you are going thru the hassle of replacing sockets you might consider just converting to octal sockets and going all 7591 ish. It’s easier to find better oxtails.
Click to expand...

I went the other way, at the time proper size 7591 didn't exist, the only thing that fit were the EH 7868. Currently I'm sitting on a supply of old production 7868 so I'm leaving the original style sockets in the S-5500.
 
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