I can no longer resist the urge....

As with most things: it depends.

The whole antenna world knows that a short, thin, uniform metal rod that is
normal to a conducting plane has an open circuit voltage at its base that is
equal to one half of the size of the incident vertically polarized E field
multiplied by the rod's length. Such an antenna has a "height" that is one
half of its physical length.

Note: open circuit voltage
Note: short - less than 0.1 WL
Note: the current distribution of the subject rod tapers linearly to
zero at the distant end of the rod
Note: the voltage or power delivered to something other than an open
circuit is not discussed
Note: many references that discuss short rods are assuming a constant
current along the rod's length - such rods have a "height" equal to their
physical length

I have dealt with approximations of the subject device. In each case,
an extremely high input impedance amplifying device is placed at the base of
the antenna that has a known voltage amplification and a 50 ohm output
impedance. Knowing that a close approximation of the open circuit voltage
is amplified by a known amount, a calibrated, tuned voltmeter (at 50 ohms)
is able to measure the size of vertically polarized E (with the usual
uncertainties). (and a bit of arithmetic)

73 Mac N8TT
--
J. Mc Laughlin; Michigan U.S.A.
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