[Elecraft] k3 switching supply

[Jim Brown]

On Wed,6/17/2015 4:55 AM, Marc Veeneman wrote:
> When I connected station ground to the power supply that went away, I think it was a ground loop.

Wrong word, correct solution.  The correct word is "bonding," and there 
ain't no such thing as a "ground loop." What there IS is a difference in 
potential between the chassis of one device and the other. When you bond 
chassis to chassis, you reduce that difference to a small value.

>   With these changes I now have no RFI from either one.

Proper station bonding is quite important, both for safety and to 
minimize noise. But a connection to EARTH, while important for lightning 
protection, is not part of a solution for hum, buzz, or RFI.

http://k9yc.com/GroundingAndAudio.pdf

73, Jim K9YC