[RFI] Please comment this picture

[Jim Brown]

On 1/3/2023 11:59 AM, David Eckhardt wrote:
> Jim, I have measured (Icom 7300) reduction of nearly 11 dB of noise 
> pickup from local sources by installing a bifilar wound common mode 
> choke in the shack to transition from common mode from the 
> transceivers/amps to differential mode of my antenna feedline.  It is 
> NOT a waste of energy, time, and money (built and measured my own).

The question was in the context of coaxial feedlines. In such a system, 
there should be zero common mode on the feedline coming into the shack 
if it is properly bonded before it enters the shack, and if our home and 
operating desk are properly bonded and grounded.

73, Jim K9YC