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Re: Topband: Unterminated WOG/BOG

To: topband@contesting.com
Subject: Re: Topband: Unterminated WOG/BOG
From: Mark <pa5mw@home.nl>
Date: Sat, 1 Jul 2017 10:18:51 +0200
List-post: <mailto:topband@contesting.com>
Hi Sean

Using BOG antennas here for >5yrs now.

150ft is a bit short, but will work. Preferably use 200-250ft. From 300ft onwards I experienced clear degeneration of the S/N advantages. Lots of info other BOG websites on the why.

I cannot comment on you zig-zag proposal, but think that like any alternative in antenna design, you win some/loose some.

Running wire in the woods will work, but it must be on floor level.
When it is 2inches and up , you will need more length (250-300ft)

Wire can be in a ditch, along cycling/walking paths, on grass, clean construction or farmground.

Black or brown insulated wire is least unobtrusive. Very thin wire even more.

Single ground rod at the feedpoint makes it a great bi-directional receiving antenna with good side-rejection. In 160m SO/LP contesting I have succesfully used only two of these to enable 4 directions.

Use a 4:1 transformer on the feedpoint (#73 binocular ferrite works great) and use common mode filtering before entering the shack.
Preferably bury the coax as much as possible.

For contesting you can consider to run the full length BOG just after sun-set and roll up early in the morning. I did that when I had to cross a path.
I can only maintain N/S directions in a ditch.

In the end it is only about signal to noise results. Less local noise pick-up, less QRM etc. And; any new quick&dirty temporally test antnna is good practice as one can never have to many antennas.

73 Mark PA5MW


On 26-6-2017 16:33, Sean Waite wrote:
I've discovered that the woods off the corner of my property give me a good
straight run where I could run a 150' or so beverage pointed directly at EU.

The difficulty is...it's not my property there, but a wooded area connected
to a neighboring apple farm. It isn't being used, but it's still a little
shady to run an antenna there.

I was thinking of getting something like this
https://www.dxengineering.com/parts/svp-sv-bog  and running a wire into the
woods.

The difficulty is that these seem to want to be terminated at the far end,
but I've seen people talking about using them unterminated. Given this
isn't my land, I'd rather not drive a ground rod on the far end - we also
have pretty rock soil and getting the rods into the ground is a bear.

-Can I only have a ground rod at the near (feed) end and just leave the far
end unterminated?
-If I ran a longer wire, but zig zagged it how would that affect the
receive ability?

I figure a black length of wire laying on the ground will go basically
un-noticed and be out of the way. Any thoughts?

Sean Waite, WA1TE
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