[Elecraft] (K3) 0.420" = SMA ?

[Brian Alsop]

Guys,

The K3 "REF IN" hole measures 0.420" diameter close as I can tell.

Normal SMA's are 0.25".

N2QT says he needed washers to mount an SMA there.

Other replies on a previous query said the K3 manual says it is "SMA"

There is no clearance on the inside for the normal BNC bulkhead 
connector because of the PC board present.  No room to fit, much less 
tighten a nut.  A BNC would be a very a loose fit in this hole anyhow.

So what connector is this hole really designed to take?

73 de Brian/K3KO