Someone more...
On Wed, 5 Jun 2002, James Moritz wrote:
With no counterpoise, the antenna loss resistance at 136kHz was 37ohms.
With the counterpoise as above, Rloss dropped to 32ohms, a reduction of
about 14%. With antenna current of 5A, 1A (ie 20%) of RF current was
returned through the counterpoise.
Part of current returning through groung is 4/5 = 0.8
And resistance 32/37=0.86
It seems if disconnect the ground loss resistance to be about
((0.86 - 0.8)/0.8)*37= 3 ohm!!!
But it is worth to isolate TX box from antenna/conterpoise system by
ferrite transformer. Loading coil should be in series with secondary
(!!!) wire of transformer, not primary.
73 de RA9MB/Alex
http://www.qsl.net/ra9mb
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