Atmosphere
In rec.radio.amateur.antenna gareth wrote:
As we all know, the atmosphere greatly affects the propagation
of radio waves, with all the various layers, and the effect of the
Sun and sunspots on propagation through the atmosphere.
Is it therefore not beyond the bounds possibility that this same atmosphere
affects the initial propagation of radio waves away from our antennae,
and that somehow is the reason why short antennae are poor radiators
compared to antennae of significant (1/4 lambda) fractions of
a wavelength?
No.
It is easily shown by a little analysis that electrically short
antennas are "poor radiators" because of their low input impedance
and all the losses associated with feeding that low impedance from
a real world source.
--
Jim Pennino
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