Hi Greg,
Four to six feet is not too high for a Beverage on 160 through 40 meters
Beverage sensitivity improves gradually with increased height and th
rear lobe and sidelobes increase (directivity degrades) gradually with
increased height.
The only Beverages I ever installed lower than seven feet was an array
of 64 Beverages each 240 feet long and only four feet high. The array
operated from 7 to 30 MHz We installed an eight foot high chain link
fence with concertina wire on top surrounding the entire 15 acre field
and covered the entire field in gravel.
73
Frank
W3LPL
----- Original Message -----
From: "Greg Chartrand via Topband" <topband@contesting.com>
To: topband@contesting.com
Sent: Wednesday, July 1, 2020 4:36:43 PM
Subject: Re: Topband: experiments with a short beverage
* 250 feet of insulated wire strung out in 030 degrees direction toward EU,
pretty straight, varying in height from 4 to 6 feet, running through thick
brush with no metal objects or artificial elements along the run.
This is a bit high for a beverage.
* 9:1 transformer at feed point with ground rod
The transformer is critical. a binocular transformer with the primary and
secondary insulated from each other is really important. Also the ground for
the coax side should not share the same ground as the wire ground, the primary
must stay independent with only the transformer coupling to the beverage.
* 300 feet of coax, mix of RG-8, MMR-400 to get to the edge of the woods from
the house
OK
* No terminating resistor
Absolutely a no-no. Your "beverage" is actually working as a 1/2 wave end fed
wire, particularly up as high as you have it. Terminate, terminate,
terminate!!! -----------You might be better off dropping the wire to the ground
as a bog, 250' is close to optimum for it; something to try....?
Greg---------------------Greg Chartrand - W7MYRichland, WA.
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