[RFI] High local noise level...

Jim Brown jim at audiosystemsgroup.com
Sat Mar 14 19:41:57 EDT 2015

On Sat,3/14/2015 3:19 PM, Kenneth G. Gordon wrote:
> Today, I connected the audio output of my transceiver, a Yaesu FT-890,
> set to AM-wide, tuned to 3580 KHz, into my computer and fired up
> Spectran.
> Spectran is exhibiting a very wide-band series of peaks in the noise
> which appear to be multiples of 60 Hz.

You are seeing harmonics of the AC power line. This is an indication of 
improper bonding of your equipment. Study 
http://k9yc.com/GroundingAndAudio.pdf The simple rules are: 1) Get power 
from everything in your station from the same AC outlet, or outlets in 
the same backbox, or from outlets whose Green wires are bonded together; 
2) Bond from chassis to chassis of every piece of equipment that is 
interconnected by short, fat copper; 3) Bond from your TX chassis to all 
the other grounds in your home.

73, Jim K9YC

More information about the RFI mailing list