On 11/28/2021 1:30 PM, Michael Black via groups.io wrote:
It depends on how susceptible the USB cable is to RFI.AND the radio. AND the computer.
Those having RFI issues should run, not walk, to buy N0AX's ARRL book on grounding and bonding, and STUDY it. Also STUDY the slide deck for talks I've done at ham radio conventions.
If an end-fed antenna doesn't have radials or a counterpoise, it will use whatever the rig is connected to in the shack as a counterpoise. Radials or a counterpoise are the other half of the antenna. AND a serious common mode choke is needed at the feedpoint of every antenna, including end-fed ones. Any antenna current flowing in the shack will cause RFI.
73, Jim K9YC