A few years ago when I started playing around with BOG antennas, I
buried a 160 foot length existing BOG 2 to 6 inches. I lost more
than 6 DB on 160 meters. On 80 meters signals went WAY down.
I did not go further with exact measurements. Lower frequencies
have deeper, less attenuated, earth penetration.
73
Bruce=K1FZ
www.qsl.net/k1fz/beveragenotes.html
On Sun, 22 Feb 2015 08:19:56 -0500, Tom W8JI <w8ji@w8ji.com> wrote:
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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