Jack Painter wrote:
Figure 2.0 illustrates the efficiency for various counterpoise systems and a
dipole above ground.
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Actually, it only shows the effects of running a counterpoise under a dipole
erected so close to the ground that it could never work properly (without a
counterpoise). It is no help in determining if adding a counterpoise under a
dipole that is already higher than one quarter wavelength above ground would
help or not. If dipole efficiency is already between 90-100%, then the
findings appear inconclusive as to whether any gain would be realized, ie:
the 1.64 factor that might be possible from a perfect dipole with minimal
earth-losses.
0.25 lambda = 40 m or ~130 ft on top band. Few of us have top band antennas
that high. Did you not notice the working frequency of 1.825 MHz?
If your antenna is already 90-100% efficient it seems fairly obvious that
there is little more to get without sacrificing omni directionality.
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