Topband: RFI - and lots of it

Jim Brown jim at audiosystemsgroup.com
Wed Oct 28 18:31:18 EDT 2015


On Wed,10/28/2015 1:49 PM, Jim Murray via Topband wrote:
> Thanks Steve.  I agree but didn't expect this problem.  Should have known this could be a problem since this is an older home that has been remodeled.  Regardless of the outcome with the power company I've been studying Jims writings on grounding and bonding and finding things that don't look right such as no ground rod for the power panel and a few elements of bonding are missing.  Looks like I'll have to straighten a few things up inside also.

That's one of many things I found wrong in the home I bought here in CA 
ten years ago. The only "ground" near the service entrance was to a hose 
faucet about 40 ft away, which was fed by PVC pipe. 240V plus neutral 
plus equipment ground was carried to a detached building with a 
"mother-in-law" apartment and garage. In that building, the only ground 
was a piece of #12 that meandered around the building for about 75 
linear feet to a single rod. I measured 1A in the green wire feeding my 
Titan power amp! All the noise on the power system neutral was going 
ground via the long connection to the second building, which radiated 
like crazy, making the QTH very noisy.

I also found one reverse-wired outlet, and an entire circuit in the 
"mother-in law" kitchen that was fed from one side of 240V and the green 
wire!

Before fixing all these problems, I heard the noise build on my HF 
mobile rig as I pulled into the driveway, and my 160M vertical, just 
outside the shack, was mondo noisy. Adding ground rods at the service 
entrance, and multiple rods in the "mother-in law" bedroom that became 
my ham shack made things a lot quieter.

The obvious advice is to never assume that ANYTHING was done right. Buy 
an outlet tester and check every outlet. Open up every box and check for 
proper bonding. Verify that there are bonds between all the systems, and 
be sure to add bonds from your radio shack to that combination of grounds.

73, Jim K9YC


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