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Old October 22nd 14, 07:22 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
gareth gareth is offline
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First recorded activity by RadioBanter: Sep 2012
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.


"gareth" wrote in message
...
"Steve" wrote in message
...
Probably proportionately more will be lost as heat as a very short
antenna will be a low impedance, therefore current, driven job and I sq*R
losses within the antenna will play their part. Apart from those
additional losses, it should radiate all that is left,


Some will be radiated, but in a short antenna, much less than with a
long antenna. That which is not radiated will reflect, or bounce off the
end and arrive back at the feed point.


If the short antenna is a dipole, then the two reflections will be
considerably out of
phase, resulting in vector cancellation, which will also contribute to
reduced
efficiency of radiation.