You are both perpetuating the confusion here by pretending that these
are two different forms of antenna.
Of course the "counterpoise" will radiate. It will radiate energy
proportional to the current in it, and the longer its length the higher
the current will be. That's EXACTLY the same case as for an off-center
fed antenna ... they are the same thing. If you drop the end of an
off-center fed dipole too close to the ground it will waste energy in
the form of ground losses as well.
Calling it a counterpoise is a misnomer.
Dave AB7E
On 1/13/2018 9:41 AM, K9MA wrote:
On 1/13/2018 07:44, Don Wilhelm wrote:
All information I have seen says that the counterpoise needed for an
EFHW is 0.05 wavelength - at 40 meters, that is about 3.5 feet.
If you make it longer than that, it becomes an offset center fed
antenna, longer than a halfwave, in other words, it is a random
length wire. Both the half wavelength wire and the counterpoise wire
will radiate.
True, and the longer the counterpoise, the more it will radiate, right
into the ground if it's just lying on the ground, so there's really no
point in a longer counterpoise for the EFHW.
One extreme case is the center-fed full wave, or "two half waves in
phase". It has the high feedpoint impedance of the EFHW (actually
about double) and has a pattern much like a dipole, but sharper. It
has a couple dB of gain over a dipole broadside but, of course, less
gain in other directions.
73,
Scott K9MA
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected]
