In article ,
wrote:

Oh, then the 'easiest' solution I'm aware of is a pogo pin soldered in a BNC
fitting, and a lathe-job threaded tube, 3/8-27 to 38-32, to mate the threads.

I'm not sure I've ever encountered 3/8-27, but I have taps for 3/8-24./ -26. /-32

Pogo pin???? What's that?

A two-piece (concentric cylinders) electrical contact. Think
"piece of brass rod, slid into a brass tube, with a spring at the
base".

See https://www.ebay.com/itm/261897100962 for one example of how
they're used. This is a JTAG connector with 8 pogo pins. It can be
pressed down onto an 8-pad through-hole pattern on the board
(preferable one populated with a machined-pin socket, although you
could probably make it work just with plated-through holes).

https://www.ebay.com/itm/SOIC-8-Spri...g/250464158353
is similar, for a SOIC pattern.