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[TowerTalk] To Ground or NOT to Ground

To: <>
Subject: [TowerTalk] To Ground or NOT to Ground
From: (Tom Rauch)
Date: Thu, 30 Apr 1998 10:25:43 +0000
To: <>
> Date:          Thu, 30 Apr 1998 00:04:41 -0400
> From:          "Jim White, K4OJ" <>

> In several go rounds on this topic a year or so ago, last I knew:
> W0UN favored grounded elements for noise (static) reasons, if memory
> serves....couple to the element top the boom to the mast and ultimately
> ground so no electrostatic stuff could be on the element......if memory
> serves

Hi Jim,

I'm as puzzled as others (like Cedric?) about all this stuff, and 
have been for years and years.

There are a few things that are very well established...

1.) A far field noise signal is no different in ANY electromagnetic 
characteristics than a signal from a transmitter or other intentional 
radiator. If you look at the far field ratio of electric to magnetic 
fields, its exactly the same from a crystal controlled 6L6 rig, a 
FT-1000, a lightning strike, or a neon sign. It certainly makes 
no difference what the source antenna is, or what you use for 
receiving the distant noise (pattern differences excluded).

2.) The near field can be dominated by either magnetic or electric 
fields, and whichever  induction field dominates is pure 
happenstance for that situation.

3.) Static charges do not make noise, only moving charges make noise. 
If the charge "moves" at the same rate your receiver passband 
accepts, you hear the noise.  So a dc grounded element or dc closed 
loop makes no difference at all, unless it stops the charge from 

One of my best performing 160 meter receiving antennas was an array 
of ten foot vertical "e-field" probes in a broadside-endfire phased 
array. It made absolutely no detectable difference at all when the 
elements were replaced by loop antennas! Nada, zero, zip.

I also did a somewhat unscientific test a few years ago. I connected 
a grounded 45-50 kV dc supply hot lead to a garden hose nozzle, and 
set it on a PVC stand. I directed a mist of charged water at 
different ten meter antennas, and watched the noise. The self-created 
precipitation static was no different on a grounded element as a 
floating element, as long as I had some kind of leak resistor.  
Without the resistor, the corona was a little less but then I would 
get big meter pinning pops when the feedline isolation capacitor 
arced over.

Insulated wire, bare wire, it all made no difference at all. The only 
thing that changed the corona noise was the addition or removal of a 
sharp point at the end of the antenna.

I suspect most of this is just what makes us all feel better about 
our antennas, like washing and waxing a car and thinking the 
gas mileage went up.

73, Tom W8JI

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