[RFI] Fwd: RFI from Carrier Heat Pump?

[Jim Brown]

On 2/15/2023 11:25 AM, Charles Plunk wrote:
> Fast forward, no RFI detected from it. I could spit on it sitting here 
> in the radio room if not for the outside wall 😄. Only thing I hear on 
> the rigs is when the natural gas ignitor kicks on for a second or so. 
> Guess I got lucky.

Whether we hear RFI from ANY source depends primarily on 1) proximity of 
the source and its wiring to ANTENNAS and 2) combined noise from other 
sources. The typical home has dozens of them -- almost everything 
plugged into the wall purchased within the last 15 years, so it's very 
common for any strong noise source to overwhelmed by the others. Thanks 
to the noise from our own homes and those of our neighbors, most of us 
are varying degrees of deaf on receive.

Proximity to radios or the shack matters primarily if we fail to 
practice proper grounding and bonding. This requires chassis-to-chassis 
bonding of everything that's part of our station, from there to all the 
other grounds for our building, including power, telco, CATV, etc. Study 
N0AX's excellent ARRL book on Grounding and Bonding, or this link.
http://k9yc.com/GroundingAndAudio.pdf

To know whether any device is noisy, we must probe around it and along 
any wires connected to it with a battery operated receiver. This link 
includes examples.

  http://k9yc.com/KillingReceiveNoise.pdf

73, Jim K9YC