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Re: Topband: First attempt at beverage antenna, not working as expected

To: topband@contesting.com
Subject: Re: Topband: First attempt at beverage antenna, not working as expected
From: Greg - ZL3IX <zl3ix@inet.net.nz>
Date: Tue, 18 Jan 2011 06:29:59 +1300
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Hi All,

I'm sure that the Epsom salts trick works well, but seems to require 
quite a high level of maintenance.  At my remote Rx site I use multiple 
ground rods to terminate my Beverages.  I find that using 3 rods, then 
bringing the termination resistance back up to the 500 ohm that it 
should be using a fixed resistor, works very well.  The total 
termination resistance then stays fairly constant through both wet and 
dry seasons.

I do also check the resistance from time to time, using a little 
portable 100 Hz AC source that I made.  The source is connected to the 
opposite end of the wire from the termination, and can therefore be used 
to check the wire continuity as well.  I have found that trying to make 
DC measurements is very unreliable, as the variable electrochemical 
effects alter the measurements quite considerably.  The 100 Hz does NOT 
give the same results as using an RF source would, but at least it 
allows a stable reference to be noted, against which future measurements 
can be compared.

73 Greg ZL3IX

On 2011-01-17 19:09, Mike Waters W0BTU wrote:
> I forget how often, Mark. I think it depended on when rain washed it away. The
> performance would fade, and a fresh application instantly restored it.
>
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK

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