[SMCARA] Couterpoise Question

[Clarke, Tom AIR4.0P NATOPS]

Bill,

I think the answer is "it depends"!  Conventional wisdom has it that the length of the radials are not as critical when on the ground or buried.  Ground conductivity gets into the act here also. Things would be quite different in Arizona!

 In your case the 8.6 foot radial is a "tuned" radial and should be in the same plane as the antenna, although not critical if it hangs vertically (although it may affect the directionality somewhat.  In the case of the 80 meter radial, again it should be elevated to function as a tuned radial, but if your situation calls for it to be on the ground, the elevation  of the feedpoint should not be added to the radial length, as it is all part of the radial length.  Since part of the counterpoise is on the ground, it will become detuned by the earth anyway.  There are several treatises in the ARRL archives concerning grounds, radials, and counterpoises.

FYI, I have a ground  mounted vertical antenna and I simply have 32,  twenty-five foot radials on the ground or slightly buried.  This works very well.  When I had this antenna mounted on a tile roof in EA7 land, I used 4 elevated,  stub-tuned radials which worked very well. Adding additional radials on the roof did not make any noticeable difference.

What kind of end fed antenna are you using?

Tom/W4OKW

-----Original Message-----
From: SMCARA [mailto:smcara-bounces at mailman.qth.net] On Behalf Of Bill Jones
Sent: Thursday, September 25, 2014 6:08 AM
To: smcara at mailman.qth.net
Subject: [SMCARA] Couterpoise Question

If I need a 65 to 70 foot counterpoise for 80 Meters and a 8.6 foot one for
10  Meters and my balun from my end-fed antenna is 10 foot up do I need to add 10 feet to the math to get the counterpoise to ground level for it to be effective. In the example of 10 meters the wire is just hanging in air.
These would be run opposite to the feedline. Thanks!

Bill
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