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Old March 4th 16, 03:09 AM posted to rec.radio.amateur.antenna,uk.radio.amateur
Wayne Wayne is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Everything you want to know about antennae ....



wrote in message ...

In rec.radio.amateur.antenna Wayne wrote:


"rickman" wrote in message ...

On 2/29/2016 1:42 PM, gareth G4SDW GQRP #3339 wrote:
"Wayne" wrote in message
...
"gareth G4SDW GQRP #3339" wrote in message
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"Wayne" wrote in message
...
There has previously on the newsgroup been a claim that shortness
makes
inefficiency.
To that I say that if for example, 100 watts is fed to a resonant HF
dipole, and 100 watts is fed to a 1 foot long dipole, both radiate 100
watts.
Different patterns, but the power radiated is the same, if you manage
to
successfully get the power to the antenna.

The ratio of radiation resistance to ohmic resistance will give the lie
to
your claim.

In my claim, equal power arrives at the long or short antenna AFTER the
ohmic resistances have already occurred.


I don't know what you mean by that. The Ohmic resistances to which I
referred
were those of the antenna rod itself.


# All practical antenna have ohmic resistance. None are perfectly
# efficient. You can design any antenna to have any efficiency you wish
# by using suitable materials even if you have to use superconductors.

I gave up. If we are talking about theoretical antennas, they are
lossless.


# Theoretical antennas have whatever loss you assign to them.

And lossless is a good way to get down to basics.