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Re: Topband: "Missing" Buried Radials for a Monopole

To: <topband@contesting.com>
Subject: Re: Topband: "Missing" Buried Radials for a Monopole
From: "Tom W8JI" <w8ji@w8ji.com>
Reply-to: Tom W8JI <w8ji@w8ji.com>
Date: Fri, 24 Aug 2012 11:22:05 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Good point, Dick.

> So while this isn't a very efficient antenna system compared to one using
> 120 x 1/4-wave buried radials spaced every 3 degrees around the monopole, 
> it
> does not show much directionality in the azimuth plane -- as might be
> anticipated for the lopsided ground system it uses

There was an AM station is Ann Arbor Michigan with the radials cut in a 
direction where the staion had too much field strength. The only thing that 
did was destabilize the array as weather changed, and slightly reduced 
efficiency in all directions. The station really had a phase monitor 
problem, but the engineer, probably out of frustration, started cutting 
radials loose.

At my present QTH on 40 meters, somewhere around 15 evenly spaced radials 
flattened off the measured field strength improvement. Even 60 radials would 
have been a waste of wire.

About 20-30 radials flattened off the 160 meter system using 1/4 wave 
verticals.

The 120 radials being "perfect" thing is obviously a myth, just like the 
idea it takes a special counterpoise to reduce losses better than a dozen 
other methods the same size.

I'm still hammering away at the counterpoise thing off and on:

http://www.w8ji.com/counterpoise_systems.htm

73 Tom 

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