[Elecraft] (Elecraft) Antenna connector

[Geoffrey Mackenzie-Kennedy]

My suggestion is that the BNC connector on the K2 should be left untouched, 
and if the antenna feeder uses RG-213 or similar an 'adapter' made from a 
length of RG-58 coax with a BNC male at one end and a N connector at the 
other end should be used. Two reasons for this (1) The RG-58 'adapter' will 
prevent the K2 disappearing due to the weight of the RG-213  (2) The K2's 
BNC connector is insulated from the rear panel and IIRC the connection 
between the coax braid and the RF board is direct via the BNC connector. 
Using a connector mounted on and in contact with the rear panel would upset 
this direct connection to some extent even assuming that a solder lug was 
placed under one of the connector's fixing nuts for a wired connection to 
the PCB input ground. Any change in performance would most likely not be 
noticeable at the operating frequencies, but there just might be a change at 
some harmonic frequency of the higher bands.

73,
Geoff
GM4ESD