I have always (almost?) run either balanced antennas with Baluns
(yagis-dipoles). My problems happened on 75 mostly with phased sloper
arrays, corner fed delta loops, and flat top 75m dipoles at 80' directly
overhead. 3 ground rods in good soil and common point shack ground and
braded ground wire fixed it. I cannot be certain that a lot of it was not on
braids of feedline coming in, but it should not have been on center fed
resonant dipoles with baluns, nor should the delta loop. It can be argued
that a sloper could use the vertical support (tower) as the primary radiator
and the sloper as the counterpoise. That could render the ground radials
below the tower useless. These were not balun fed. I had always assumed that
I was in the path of a good level of radiation and not that I had feedline
radiating. I have learned something. Thanks, Sam
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
Behalf Of Bill, W6WRT
Sent: Tuesday, April 05, 2011 10:59 AM
To: amps@contesting.com
Subject: Re: [Amps] 2 more questions-- electrical
ORIGINAL MESSAGE:
On Tue, 5 Apr 2011 10:31:21 -0400, "Sam Carpenter"
<sam@owenscommunication.com> wrote:
>I also notice that he asked about "Shack" ground. Anyone who has run QRO
and
>used only electrical grounds gets RF burns to the lips on a mic, to the
>underside of the forearm on the corners of chairs and desks. Sometimes
quite
>embarrassing on a voice peak to burn the hell out of your self and create
>another unwanted voice peak. The electric panel is not a suitable shack
>"RF"ground and things get uglier the higher in power you go.
REPLY:
If you are getting RF in the shack, you do not have a grounding problem,
you have an antenna problem. You do NOT need an RF ground at your shack
in any way. The only grounds your shack needs are for safety of the AC
mains and for lightning.
RF in the shack problems indicate an unbalance in the antenna and/or
feedline system and can almost always be cured by proper application of
a balun or unun.
RF energy is expensive to generate. Do not waste it by running it
through dirt. Get it up in the air where it belongs.
73, Bill W6WRT
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