All,

I have been experimenting with various loaded antennas to use in my relatively
limited space. For this I assumed the two arms of a dipole must be identical to
support resonance, this assumption has not been supported by modeling.

Actual model runs show that if the two arms of a dipole are close then there is
sufficient interaction that they will combine to form a single resonance. The
model below shows a simple example of this. The loads and length of the arms are
not equal, however nec predicts a single resonance at about 3.5 MHz. Changes of
10 to 20 percent around resonance seem to create one resonance.

Is there an explanation for this?

Thanks - Dan kb0qil


CM 75 m loaded dipole
CM copper conductivity
CE
GW 1 31 4 0 8 0 0 8 .001
GW 2 11 0 0 8 -6 0 8 .001
GE 0
LD 4 1 16 16 3 2500
LD 4 2 5 5 3 2000
EX 0 1 30 0 1 0
GN 2 0 0 0 13 5.e-3
FR 0 1 0 0 3.543 0
EN


Frank wrote:
"Cecil Moore" wrote in message
. com...

Frank wrote:

To be exact; a 16 ft dipole would need to be loaded with inductors of Q =
78 for a 0.99% efficiency. The gain is therefore -18.3 dBi.

Sounds about right. Hamsticks are about 12 dB down
from a good screwdriver on 75m.
--
73, Cecil http://www.qsl.net/w5dxp


I wonder what the efficiency of a Miracle Whip is?

73, Frank