Dick, PA0SE, and others have recently been using a multiplication
factor of 1.83dB to obtain ERP. This is the supposed gain of a
vertical antenna over a dipole because of ground reflection.
Is this really vaild? Ground reflection surely must depend upon:
(1) The efficiency of the local ground connection and
(2) The conductivity of the ground
both of which must have a much greater effect on the tiny (in terms
of wavelength) antennas we use, than a full quarter-wave. Isn't the
1.83dB a theoretical improvement that is not achieved in practice?
I am sure I would prefer to run a dipole on 136kHz, than a 14m
vertical.
Is this +1.83dB really useful at all? Or have I misunderstood?
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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