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Old September 23rd 07, 07:29 PM posted to rec.radio.amateur.antenna
Richard Fry Richard Fry is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 440
Default Aerial grounding and QRM pick-up: theory & practice

On Sep 23, 11:18 am, art wrote:
In comparing two antennas with similar omni direction radiation field
I state that gain in the field is indicative of increased radiadion ...


....yes, but radiation only in limited az/el sectors, at the expense of
loss of radiation in the other sectors.

The field gain in a particular direction is due to the change in
pattern shape, not an increased radiation efficiency of the "better"
antenna.

For the same input power accepted by different antennas, the total
power radiated into the volume of space is the same, no matter what
the shapes of their respective radiation envelopes.