Topband: Beverages near the ocean

[Milt -- N5IA]

Mike,

It is not that they are near an ocean.  It is if the conductivity of the 
salt water is near enough under the beverage element such that the salt 
water (or salted earth ie. salt marsh) is acting as the other conductor of 
the "twin lead" transmission line (the Bev wire is one conductor in the 
transmission line and the earth is the other conductor).

If the Beverage is far enough above such conductive earth so that the "earth 
conductor" is a bed of sand, coral, or non-salty earth, it will perform in 
the classic fashion.

This was proved at XZ0A in 2000.  The bevy of Beverages were constructed 
over the top of the island through jungle foilage for the most part.  There 
was considerable earth and probably rock below the Beverages down to the sea 
level.  The antennas performed excellently.

I also constructed a mirror image of the Bev oriented to JA, but installed 
it along the shore line with nothing but shore rock at low tide and sea 
water at high tide.  This antenna was an absolute dummy load whereas its 
twin, located a couple of hundred feet distant, was performing normally.

Three years ago on Ducie at VP6DX the Beverages were all constructed over 
the island with the ends terminating within ~ 30 feet of the open ocean or 
lagoon.  The maximum elevation of Ducie is about 15 feet AMSL.  The surface 
composition of the atoll is a deep bed of coral fragments and dead shell 
pieces.

As evidenced by the accomplishments of the low band operators during the 
peak of the austral summer, the Beverages worked extremely well.

This is the Beverage operational theory as I understand it, and have proven 
conclusively to myself to be true.  Your mileage may vary.

73 de Milt, N5IA


-----Original Message----- 
From: Mike Fatchett W0MU
Sent: Thursday, April 21, 2011 8:36 AM
To: topband at contesting.com
Subject: Topband: Beverages near the ocean

I was reading ON4UN's Low Band DXing Book and ran across a comment he
made about beverages not working near the ocean and the Heard Is folks
could never get one working.  I know we used one from V47 and it worked
great.  It was located probably no more than 300 ft from the water.

This is the first time I have read or heard of this phenomenon.  Have
others had issues with beverages near the ocean?
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK


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