Mike Monett wrote:

Hi Roy,

There's lots of room for confusion. The Kings tool FAQ implies the
center contact diameter got smaller when the pin was redesigned and
the old crimp die set would not work:

. . .

However, another manufacturer claims their new 75 ohm hardware is
interchangeable with 50 ohm connectors:

. . .

If your junkbox is anything like mine, it may have stuff purchased
20 years ago mixed with more recent purchases. So it might be
worthwhile to check carefully before mating different hardware.

For sure. It looks like it's not safe to mate a 75 ohm connector with
anything, even another 75 ohm connector, without checking pin diameter.

Roy Lewallen, W7EL