Last
possibility to improve the efficiency of the Beverage Antenna
could be increasing the height of the horizontal wire to 4- meters
above the ground. In theory this way should bring to multi beam
DD at the high frequencies bands (because the vertical wires of
the antenna take part at creation DD) and to some difference of
the antenna impedance from the impedance of the termination load.
Figure 31 shows design of the Beverage Antenna with horizontal wire placed at
height 4 meter above the ground.
. Parameters of the antenna were simulated with NEC
for MMANA. Table
4 shows the data for the antenna. Maxima gain is given
to the radiation angle at where it is.
Theoretical data show that the antenna gain improved
at all Bands. However because the antenna impedance not to be
close to the impedance of the termination load there would difficulties
with matching of the antenna at 12 and 10- meter Bands.
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Figure 30
DD of my Beverage
Antenna with additional wire between feeding transformer and termination
load at 10- Meter Band
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