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Old September 11th 15, 02:16 AM posted to rec.radio.amateur.antenna
[email protected] nm5k@wt.net is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 757
Default The nature of Free Space (Once called, "The Lumeniferous Aether")

On Thursday, September 10, 2015 at 6:06:33 PM UTC-5, gareth wrote:
wrote in message
...
On Thursday, September 10, 2015 at 5:27:41 AM UTC-5, gareth wrote:
What is the nature of free space such that it requires antennae to be at
least 1/4 wave
before accepting radiation efficiently?


Ding, ding, ding. Totally false statement.
Don't pass go, don't collect $200.


Convince yourself by calculating the retarded potential from a far field
when
the same field strength comes from a dipole and when it comes from a short
antenna.
You find that there has to be more power fed into the short antenna
(irrespective of
feed impedances and ohmic resistances) to achieve that same field strength.


To put it plainly in a language you can likely understand, bull****!

If you feed a 1/2 wave dipole with 100 watts, almost all of that power
will be radiated by the antenna.

If you feed a 1/10 wave dipole with 100 watts, almost all of that power
will be radiated by the antenna.
Any difference between the two would be so small as likely to be hard to
measure. This is etched in stone theory known for many years.