[RFI] Station ground - more

[Jim Brown]

On Wed,9/28/2016 10:34 AM, Kenneth G. Gordon wrote:
> A contributing issue is, of course, that my only present antenna is a 
> vertical mounted within less than 10 feet from the new addition, and 
> that I am often running a kW output.

I suspect THAT'S the real issue -- the antenna is working as an antenna, 
so it radiates into stuff near it. BUT -- another VERY important issue 
is that we MUST provide a good counterpoise for the antenna, so that 
return current flows in the counterpoise, not in building ground wiring.


> However, I have run into at least one instance where a "ground" wire 
> (which was connected to a PLASTIC water pipe !!!!) was resonant at 40 
> meters and when I finally found this idiocy, disconnected that wire, 
> ran a much shorter wire to a PROPER ground system (3 rods as 
> previously described) the RFI I had been experiencing was gone.

Yes. I ran into exactly that in the home I bought here in W6 ten years 
ago. It was the only "ground" at the power entry!  My shack is in a 
second building, ground was carried to it, and there WAS a ground there, 
although it was VERY badly done.

With help from my neighbor, K6XX, we installed a completely new ground 
system for both buildings.  Three driven rods for the main power entry, 
about eight rods for the second building, which houses my shack. Before 
we did that, I had a lot of noise coming in on the neutral from the 
street. It didn't get to ground until it hit the 2nd building about 150 
ft of wire away from the service entrance. Putting those rods on the 
service reduced that a lot. Before fixing it, that noise current ran 
through that 150 ft or so of wire to get to ground at a single rod next 
to the shack, so it radiated into my antennas.

Another fundamental rule (human nature) -- NEVER assume that ANYTHING is 
done right, even if it was done by a licensed electrician. Some are 
better informed that others, and we human beings are well known for 
screwing up. Anyone who says he doesn't is either a massive egotist or 
is lying. :)

73, Jim K9YC