On 12/3/2021 3:53 PM, Andrew Ikin wrote:
I guess what Chuck means, is a Ground loop due to the antenna end of the coax. screen being connected to Earth thus causing the feeder shield to become a loop antenna with the ground RF return path to Rx. Hence, resulting in excess noise pick-up.
A serious common mode choke at the feedpoint is critical for this, effectively disconnecting the coax shield from the antenna for common mode current. But proper grounding and bonding in the shack and throughout the home are critical -- a primary cause of RF in the shack is failure to do that.
There are differences with practice in the UK and EU with respect to connection of earth electrodes. This set of slides shows proper implementation in North America, which properly considers both power and antennas with respect to lightning safety. The laws of physics don't change at the water's edge. :)
http://k9yc.com/GroundingAndAudio.pdf 73, Jim K9YC _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
