Hi all,

I just bought a B&K 470 crt tester of ebay, and tested a few tube with it (with the #23 adaptor) and then I tried to test a crappy 1995 zenith , still with the #23 adapter, then nothing... I was able to set heater voltage and G1 voltage , but not the G2, and of course I could not test the guns... One thing I noticed is the #23 adapter that I placed on the neck of the tube was very loose , as in "if you touch it it will fall" loose. Could that be the problem? Is it common to find a tube where the adaptor for it is so loose that you can never test it right?

Thanks!

Carl

Sure it's possible. The most often used adapters are usually a little worn out and don't fit tightly.

Sure it's possible. The most often used adapters are usually a little worn out and don't fit tightly.
50+ years ago, I bought a used B&K CRT checker/rejuvenator. It only had one socket and it was loose. It was the socket that fit a 10BP4, 12LP4 etc.
Most of the techs, used to salvage a socket from a scrap set or from a brightener and splice the leads.
It's just history repeating itself. :boring:

The #23 socket on my tester is loose on some tubes and I have to hold it a certain way in order to get it to make contact. Maybe I'll one day make one from a socket from a scrap board; but, these days, I find myself not needing to test tubes that recent. Up until a few years ago, I was constantly testing tubes that used socket #23. That's the most common socket for inline CRT's made between the late '70's and the end of the CRT TV era. The last time I checked with B&K, they were very proud of their socket adapters. The other common color sockets were #31 that fits many later smaller screen inline tubes, #3 that fits most rectangular delta gun color tubes, #20 that fits EFL gun tubes found in Zenith, Sylvania, and Magnavox sets from the late '70's-early '80's, and #24 that fits most '80's RCA inline CRT's. I think my #3 and #31 are a little loose, as well. Oddly, B&K never made a socket adapter for later Sony Trinitron CRT's; so, I made my own from a socket from a junk board and the proper molex connector.