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Re: Topband: Dogleg BOG antenna.

To: Max Cotton <airradio@dsl.pipex.com>
Subject: Re: Topband: Dogleg BOG antenna.
From: Guy Olinger K2AV <olinger@bellsouth.net>
Date: Sat, 22 Sep 2012 14:17:54 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
BOGs can be as short as 195 feet for 160.  They do NOT work the same
way as beverages because the velocity factor laying against ground, or
in it, is so low.  VF on BOGs has been measured as low as 45%, more
often around here 55-65 percent. On longer BOGs in the desired
direction this can cause phase on the wire to be opposite phase
incoming at points along the wire. Depending on ground and whatever,
longer BOGs can lose front-to-back entirely or even reverse pattern.
Folks have had good success around here with 200 to 225 foot BOGs.
These generally have good F/B and usually quite good local noise
quieting.  Remember to get the BOG down next to the dirt.

You may need a preamp for a BOG.

73, Guy.

On Sat, Sep 22, 2012 at 10:59 AM, Max Cotton <airradio@dsl.pipex.com> wrote:
> I am going to try to place a BOG antenna in my local neighbourhood, as I 
> don't have a 650+ foot garden I thought the most inconspicuous antenna would 
> be a BOG, however I have to 'Dogleg' it, it has to run for 200 feet North, 
> then 200 feet East and the remainder North again, I only have a maximum run 
> of 700 feet. I will terminate it with a 200-470 Ohm (select test) resistor at 
> the far end, I have to run this along a wooden fence line opposite a metal 
> mesh fence about 10-15 feet away for the entire run, this is towards the 
> East. The mesh fence is enclosing an industrial area with a footpath running 
> around that enclosure. My intended BOG will be on the side of this footpath 
> away from the metal fence. Maybe I am wasting my time, has anyone done 
> anything like this, I do have a North/South 'Inverted L' antenna but it is 
> not brilliant for TopBand as I can only ever hear UK and EU stations and 
> normally not even those. I can base load the 'L' but that is not brilliant. 
> Ground conduc
 ti
>  vity is good as I am about a mile away from a river and 3 miles from the 
> sea, good for HF but maybe not so good for LF bands. Maybe just adding a few 
> more topband radials to my 'L'  may work for the moment. Ideas on this 
> anyone? QTH is South England.
> 73 Max
> M0GHQ
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK

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