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Re: Topband: Best Height Above Ground for a Beverage RX Antenna

To: <>, <>
Subject: Re: Topband: Best Height Above Ground for a Beverage RX Antenna
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Wed, 10 Jan 2007 18:07:04 -0500
List-post: <>
>I am curious if there are directional improvements to be 
>gained with Beverage
> antennas with respect to height above ground? What changes 
> at 6 ft, 8 ft or 10
> ft? How important is it to have the height consistent over 
> the entire length of
> the Beverage?

I don't find much difference with height as long as height 
is less than .02 wavelengths or so.  This is for long 
Beverages over what probably is medium conductivity earth.

When Beverages are short or poorly terminated a lower height 
will help because they have slower wave velocity. This 
increases the electrical length, and reduces vertical end 
contribution that will deteriorate pattern on a short high 
Beverage (the EWE effect). A low height antenna also has 
more distributed loss, and that means it can't be as long as 
a higher antenna before it runs out of current at the far 

This is my observation from locations where skywave noise 
dominates the noise floor, not local noise.

My ~5-6  foot high antennas are not noticeably different 
than 10 foot high antennas on 160, but the lower ones are 
noticeably better on 40 meters.

If you are looking for a sweet spot there probably isn't 
one, and I would do a side-by-side test with equalized 
levels.... NOT just looking at noise....because noise and 
signals will both be weaker on a lower height antenna and 
that can easily give the impression the lower antenna is 
better. A lower antenna will be always quieter...but it will 
also have lower signal levels.

73 Tom 

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