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Old September 22nd 07, 07:17 PM posted to rec.radio.amateur.antenna
art art is offline
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First recorded activity by RadioBanter: Sep 2006
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Default Aerial grounding and QRM pick-up: theory & practice

On 22 Sep, 07:22, "Richard Fry" wrote:
"art" wrote

The most efficient radiator is one wave length long where
it is considered to be in equilibrium with a parallel electrical
cuircuit.
For most efficient radiation both the capacitance and the
inductance must act as a energy storage such that when
the terminals are shorted the energy is released in a burst
such that radiation can begin. ... In the case of a fractional
wave length radiator the pendulum type radiation is not
available for radiation


___________

Note (for one example of many) that in an antenna system consisting of a
1/2-wave, center-fed dipole driven by a matched, balanced transmission line,
the dipole itself radiates virtually all of the r-f energy present at the
antenna feedpoint.

The radiation efficiency of a system as in the above example, but using a
full wave dipole is no better than the 1/2-wave version, other things equal.
The full wave version just has a different radiation pattern.

RF