We were shocked to find that the existing 1/4 wl performed better than the
much taller Vertical.
The link below compares the elevation patterns of monopoles ranging from a
1/4-wave to 5/8-wave in height. These are the patterns "launched" by these
monopoles as they exist a few wavelengths from their base.
It can be seen that the taller monopoles have greater fields in and near the
horizontal plane, but their fields at higher angles are not as great as from
the shorter monopoles.
For some propagation conditions and skip distances, shorter monopoles might
produce higher skywave fields, for a given applied power.
But taller monopoles (up to 5/8-wave) always produce greater groundwave and
low-angle fields than shorter monopoles, for a given applied power.
http://s20.postimg.org/olcquv94d/Monopole_Elev_Patterns.gif
RF
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Topband Reflector
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