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Re: [Amps] Amp causing RFI

Subject: Re: [Amps] Amp causing RFI
From: John Simmons <>
Date: Tue, 4 Feb 2020 10:28:32 -0600
List-post: <>
I recommend you read the ARRL book 'Grounding and bonding'. I also highly recommend you connect to ground rods with exothermic welding.

-de John NI0K

Richard Solomon wrote on 2/4/2020 10:20 AM:
I agree with Glen. In my case a well
working system all of a sudden became
"wonky". RF Feedback, etc.

Turned out the ground lead connection
outside had loosened up. Re-tightening
the lead on the ground rod cured all my


73, Dick, W1KSZ

On Tue, Feb 4, 2020 at 9:10 AM Glen Zook via Amps <>

Having spent over 30-years as a telecommunications consultant, and having
specialties in lightning protection and r.f. grounding, I say that adding
ground rods, etc., is NOT balderdash!  No, adding such does not always
produce measurable results.  However, the majority of times adding external
grounding does contribute favorably.
There are PROPER methods of installing coaxial cable.  NFPA NEC (National
Electrical Code) requires that the coaxial cable shield be connected to a
ground rod at the point where it enters the building.  This is for
lightning protection as well as providing an r.f. grounding point.  Also,
when the cable is installed on a tower, mast, etc., the shield needs to be
grounded to that structure as near the antenna as possible and at the point
the cable leaves the structure to enter the building.  In addition, if the
structure is higher than around 100-feet, the shield needs to be grounded
every 50-feet to 75-feet along the structure.
All "other" ground rods, etc., MUST also be connected to the AC mains
ground.  There are several reasons for this of which lightning protection
is foremost.
Way too many seem to think that the 3rd wire in the AC wiring in their
house provides sufficient grounding.  Sometimes it does and, more times
than not, there can be problems on various bands caused by the length of
the wire between the outlet and the AC mains ground rod.
The whole idea is to get the lowest impedance path to ground.  When just
wire is concerned, the length of the lead needs to be no more than around
4-feet long and shorter is better.  You can increase the length of the
grounding path by using something like aluminum flashing which is available
in widths from around 4-inches wide to more than 36-inches wide.  Aluminum
is not as conductive as copper.  However, it is much cheaper and having
wider widths overrides the conductivity.
Just get the flashing as near the ground rod as possible (usually on the
inside of the building), and then a short piece of large diameter wire
through the building wall to the ground rod.
There are other things, like using chemical ground rods, that can
definitely improve r.f. grounding.  One just has to do as much as possible
to achieve a good grounding system.  Of course, the more that the
individual can do themselves, the cash outlay is reduced.
Glen, K9STH

     On Monday, February 3, 2020, 09:57:16 PM CST, Jim Brown <> wrote:
Balderdash. The earth is not a sump into which noise, RFI, and other
trash is poured. Comments like this bring to mind the infinite number of
monkeys and typewriters producing Shakespeare.

73, Jim K9YC

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