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Re: Topband: Soliciting suggestions on our receive antennas for 5X8C

To: "Dave" <davek4sv@yahoo.com>, <topband@contesting.com>
Subject: Re: Topband: Soliciting suggestions on our receive antennas for 5X8C
From: "George" <w8uvz@voyager.net>
Date: Sun, 10 Feb 2013 12:48:26 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>

Hi Dave

Your dilemma sounds very much like the one described by Robin, WA6CDR during the XZ0N operation some years ago.
I hope he will weigh in on helping with a solution.

Water can be your friend on tx but not always on rx. AA7JV on his various trips has also experienced this, I believe. Hopefully, George will comment, too,
Quick ideas:

Get beverages away from the water as much as possible. Believe this is what XZ0N ultimately did.
Experiment with gain ground independent systems.  Add a second flag in 
broadside or endfire config sounds like the easiest possibility.
I'll let the experts comment further.

And know that the tx signal is good. I.E. good copy into W8 on topband last eve from 23Z for nearly 90 min according to a local caller who could not break the EU hold, hi.
GL

73  George  W8UVZ





Hi All,

My team is currently on DXpedition to Uganda 5X8C

We have erected receive antennas here in 5X with very poor success. W e have used the same antennas at other places with great success. Please read below and if you can offer some constructive suggestions please reply to me and copy reflector. Davek4sv@yahoo.com

We are experiencing some weird problems with our receive antennas. We have a beverage about 540 feet long, terminated properly about 5 to 6 feet over the ground. I have built plenty of these at my house, they all work. This one here does not. It hears noise but no signals. Once In a while you can hears signals.
So put you're receive antenna hat on.  We suspect the ground is the problem. 
We are located on the shore of Victoria Lake at a resort.  The soil appears 
to be sandy but with fresh water lake nearby. 200 feet.  The beverage is in 
the clear away from large metal objects.
With a 510 ohm termination we measure about 235 ohms when looking across the 
termination resistor.  Using resistor theory essentially we have two 
resistances in parallel.  The wire , termination transformer, ground rods 
and ground are about 500 ohms.  Having not measured this at home I'm not 
sure if this is too low or too high of resistance.
We erected a Flag 29x14 feet mounted just above the ground.  This is 
purported to be ground independent.  Our tests last night indicate this 
antenna is not hearing very well either.
We are soliciting suggestions.  We only have a small amount of wire and 
other antenna stuff, no Home Depot or Radio Shack around.  Perhaps we can 
build a ground independent antenna that does not care what it sits on.
We have or can source some wooden poles to make wire radiators.

The 5X8C team thanks you in I



Thank You in Advance,

Dave Anderson, 5X/K4SV

Sent from my iPad in Uganda
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