Topband: BOG near salt water

[Guy Olinger K2AV]

When you say "NOT work", you probably need to specifically list the
diminished performance attribute due to more conductive media underneath.

It is very easy to model a BOG over more conductive media. It should be
noted that the ability to form a *pattern* is retained, but the
*sensitivity* is diminished.

In the case that other RX antennas are less desirable for whatever reason,
it would be good to know that a BOG still could be used likely requiring a
remote RX amp, and would still have enough pattern to do the necessary
business of reducing side and rear reception of unwanted noise and signals.

BOGs have an unpredictable success rate mostly due to not taking steps to
deal with the large variation in velocity factor from site to individual
site, and a BOG being able to form a single direction pattern with
significant front-to-back ratio only on one band.

The pattern of a well designed BOG is quite similar to a K9AY. This would
still be true over salt muck along with the need for amplification.

73, Guy K2AV

On Wednesday, January 6, 2016, Milt <miltn5ia at gmail.com
<javascript:_e(%7B%7D,'cvml','miltn5ia at gmail.com');>> wrote:

> Val,
>
> Beverages of any type will NOT work over salt water or earth where the
> chemical makeup of the earth produces a highly conductive material.
>
> Here is the way I understand the theory.
>
> The Beverage works on the principle of a two wire transmission line where
> one side of the transmission line is your Beverage wire and the other side
> is the earth.
>
> The wire half has RF voltage induced in it by 'tilting' of the wave due to
> the difference in the velocity factor of the 2 halves of the 'transmission
> line'.  The signal travels faster in the wire than it does in the earth,
> producing the miniscule amount of RF voltage in the wire, which is
> impedance matched to your coaxial cable.
>
> If the medium which comprises the other half of your Beverage system has a
> VF at or nearly so the same as your wire half, no RF voltage is produces
> and you will NOT have any signal.
>
> Congratulations on your success.  It means the earth comprising the other
> half of your BOG is not salt saturated.  You are getting signal tilt
> producing an RF voltage, and therefore signals.
>
> If you were to move the BOG over the salt water and have your grounds at
> each end connected to the salt you will find that there will be for all
> intents and purposes ZERO signal produced.  It is then truly just a
> balanced open wire feed line and nothing else.
>
> Keep up the good work.  Always try and prove things for your self.  That
> is what it is all about.
>
> 73, and good luck, de Milt, N5IA
>
>
> -----Original Message----- From: Hugh Valentine
> Sent: Tuesday, January 05, 2016 9:15 PM
> To: TopBand
> Subject: Topband: BOG near salt water
>
> Some say a BOG is not effective at/over salt water.
>
> For grins I installed a 200’ BOG to Europe.  4:1 Binocular XFMR,  #18
> single wire, (92 Ohm Termination= 1.1:1 SWR on RG6 cable) 4’ Ground Rods,
> No radials.
> Works about same as K9AY.  Maybe 8DB down in sig strength.
> Installed approximately from 1’ to a maximum of 30’ from salt water.
>
> I would say it works and can be installed rapidly.
>
> Val
> N4RJ
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