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Re: Topband: BOG antennas

To: "topband@contesting.com" <topband@contesting.com>
Subject: Re: Topband: BOG antennas
From: Jeff Wilson <jjw5257@yahoo.ca>
Reply-to: Jeff Wilson <jjw5257@yahoo.ca>
Date: Thu, 2 Apr 2015 01:19:53 +0000 (UTC)
List-post: <topband@contesting.com">mailto:topband@contesting.com>
    I put a BOG "down" for this winters DX season on 160m and was very 
impressed with it, compared to my three 550ft Beverages (NW, NE, S).  I did not 
have the SW direction covered, so I put up this BOG just after the ARRL 160m 
contest as it's need was evident following the difficulty hearing on my TX 
antenna.  So I collected what I had on hand and got to work just before a big 
snow storm.  No more 8ft rebar for Beverage supports, so I went with a BOG for 
the first time.

VE3CV's BOG:
I used 200 feet of #12 gauge stranded insulated electrial wire strung tight 
between two 4ft groundrods (3/4 galvanized conduit for one and 3/4 copper pipe 
for the other) across a plowed field, so that much of the antenna was in the 
air with furrows beneath it.    The far end had 3 - 50ft galvanized fence wire 
radials added - one in line with the BOG and the other two 90 deg to either 
side. The BOG was attached to each ground rod via strain egg insulators and 
3/16" dacron line to tighten it and provide slack to the ends that were then 
electrically connected at the acorn connector on the ground rod (about 6 inches 
above ground).

 The BOG was covered with 2 feet of snow all winter which did not reduce 
effectiveness.  The termination resistor was 220 ohm (1 watt) - will try higher 
value 270 ohm) next year.  The matching transformer was 2.78:1 or 3 turns 
primary and 5 turns secondary using #26 magnet wire and a binocular core. (as 
per chart available on W0BTU's great web page).  I used about 130 feet of RG-6 
and F connectors to feed to the shack.  I have a DXE preamp, but rarely used it 
and elected to turn the volume to 3/4 maximum with my hand on the RF gain 
control of my FT-1000MP  to save my ears from the tuner uppers!  This was 
pointed to Southern California from my Southern Ontario location (265 deg) and 
worked amazingly well to pullout the US west coast, VK, ZL, XE, KH6, etc.  This 
BOG really saved my ears and helped put lots of station in the log that I would 
have missed.
It worked on all bands and was probably best on 80m, based on stability of the 
SWR:MHz - SWR
1.8 - 4.71.85 - 4.41.9 - 4.22.0 - 3.6
3.5 - 3.23.6 - 3.33.7 - 3.33.8 - 3.33.9 - 3.34.0 - 3.2
7.0 - 2.57.1 - 2.47.2 - 2.37.3 - 2.27.4 - 2.0
10.1 - 2.510.15 - 2.4
Hope this helps Filipe
73Jeff VE3CV


Message: 1
Date: Wed, 1 Apr 2015 18:09:26 +0200
From: Filipe Lopes <ct1ilt@gmail.com>
To: Frank Donovan <donovanf@starpower.net>
Cc: topband <topband@contesting.com>
Subject: Re: Topband: BOG antennas
Message-ID:
    <CAFQcihSaDMx=C90oYysV8=wUyTTgMna=CzzU2PSrxr=mzLrqtQ@mail.gmail.com>
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Thank you Frank. Will have a look at it.

73's Filipe Lopes
CT1ILT - CR6K
F4VPX - TM3M

2015-04-01 16:55 GMT+02:00 <donovanf@starpower.net>:

> Hi Felipe,
>
> Suggest you examine this website:
>
> http://n4dj.com/Beverage.html
>
> 73
> Frank
> W3LPL
>
> ------------------------------
> *From: *"Filipe Lopes" <ct1ilt@gmail.com>
> *To: *"k1fz" <k1fz@myfairpoint.net>
> *Cc: *"topband" <topband@contesting.com>
> *Sent: *Wednesday, April 1, 2015 3:18:01 PM
> *Subject: *Re: Topband: BOG antennas
>
>
> Hello Bruce,
>
> This is a very interesting subject.
>
> I am about to "maybe" test a BOG here at my French QTH and I am wondering
> if there are any tests made with best terminating resistance (235ohm? )
> should I use a 9:1 transformer or 10:1 ?
>
> how does it perform compared to a usuall beverage?
>
> Can I cross 2 BOGs for 2 directions or more? will this affect the antenna
> pattern?
>
> I recently built an W7IUV preamp, will it be OK for the BOG ?
>
> Thanks in advance.
>
>
> 73's Filipe Lopes
> CT1ILT - CR6K
> F4VPX - TM3M
>
> 2015-04-01 16:43 GMT+02:00 k1fz <k1fz@myfairpoint.net>:
>
> > To BOG, or not to BOG, that is the question.
> >
> > Many are aware of the good, and bad points of the antenna.
> >
> > Good:
> > Is out of sight.
> > Requires a small space to function well
> > Typically has less noise than an above ground Beverage
> > As disturbed condx (QRN crashes) begin, it can be the quietest antenna.
> >
> > Bad
> > The Pattern can be poor if its too long.
> > Can be tough on a lawn mower.
> >
> > Note: Above ground Beverage antennas can cross as the low ~470 ohm
> > impedances do not couple well.
> > A typical BOG antenna has an even lower  impedance of ~235 ohms and
> really
> > does not couple well to
> > other antennas, metal objects. ( I still avoid going over the radial
> > field.)
> >
> >
> > 73
> > Bruce-K1FZ
> > For more info, try a BOG antennas search.
> >
> > Not an April 1st joke !
> > _________________
> > Topband Reflector Archives - http://www.contesting.com/_topband
> >
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>


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