I highly doubt any NEC based model predicts an accurate pattern for wires
buried in dirt, in ground contact, or very near normal earth.
It would mostly be a case of GI =GO.
73 Tom
----- Original Message -----
From: "James Wolf" <jbwolf@comcast.net>
To: "'Mike Waters'" <mikewate@gmail.com>
Cc: "'topband'" <topband@contesting.com>
Sent: Saturday, February 21, 2015 8:50 PM
Subject: Re: Topband: Modeling a BOG
Mike,
The reason the beverage wire in the model is 2 ft. below the surface is to
have it away from the ground somewhat and have a nice segment length from
the wire to ground on each end. The model shows only about 2 dB
difference in gain and no pattern difference between the wire 1” below
ground and 2ft., which I suspect could be correct for 160 meter
frequencies. Of course, the pattern is the problem.
In practice, I would lay it on the ground and after a few years, it would
be just below the surface.
Hmmm. BBG – Beverage Below Ground.
Jim – KR9U
From: Mike Waters [mailto:mikewate@gmail.com]
Sent: Saturday, February 21, 2015 8:26 PM
To: jbwolf@comcast.net
Cc: topband
Subject: Re: Topband: Modeling a BOG
I have never heard of anyone burying a BOG. The radials could be buried an
inch or so, but a BOG should lay on the ground or slightly above. 2 ft. is
two feet too deep.
About 200' is a common length for a BOG on 160.
73, Mike
www.w0btu.com
On Sat, Feb 21, 2015 at 6:51 PM, James Wolf <jbwolf@comcast.net> wrote:
I am trying to model a BOG (Beverage On or in the Ground). ... As soon as
I drop the antenna below ground level, approx. 2 ft. without errors, I
lose all indication of directivity except for a few dB. I have tried
different lengths from 200 ft. to 800 ft.
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