7JP4 Adapter

[Chris K]

I'm confused (again!). I have a 7JP4 CRT that needs a special adapter to test it due to it being an electrostatic tube. Yes I can test it in a working chassis or I could buy a Precision CR-30 tester but I don't have access to either. There's a strange item I can buy listed as an adapter socket for the B&K tester I have (465). The socket is called a B&K Precision CR-30 socket. I looked up Precision CR-30 and it's an instrument so...is this socket meant to adapt the B&K testers to test tubes like the 7JP4?..It's NOS sealed in the box so the seller won't destroy the seal so I can see it visually. Does anyone know what's up with this? If the socket IS an adapter for tubes like 7JP4 testing on a B&K, will the base match the 465's connecter to my 465 instrument? I guess B&K went from a pin and socket connecter at some point to something much smaller.