Short antennae - a reprise
"Jerry Stuckle" wrote in message ...
On 11/4/2014 7:55 PM, Wayne wrote:
"rickman" wrote in message ...
On 11/4/2014 12:48 PM, gareth wrote:
If short antennae radiate all the power that is fed to them, then why
would
anyone use long antennae, because the first part of such an antenna, the
short
part, would radiate all the power, and then there'd be nothing left
for the
extra bit, making up the rest of the long antenna, to do?
The answer is, of course, because it is more difficult to feed a short
antenna
because of its reactance.
So, whence does this reactance arise?
Simple.
It is the power that has NOT been all radiated by the short antenna
arriving
back at
the feed point with an awkward phase relationship with the incident
power.
What happens to that power that has not ALL been radiated when it arrives
back
at the feed point?
Simple.
It passes back into the matching network, which, together with the short
bit, form
the resonant artefact, where much of it disappears as heat in the
matching
network
before being fed back to the short antenna to start all over again.
Now, Stephen Thomas Cole, that well-respected font of all technical
knowledge over
in uk.radio.amateur is saying that all you Yanks are a bunch of dopes
if you
do not understand
the above, so take it up with him over there.
# It is so amazing how a simple post of nonsense will make all the
# gullible members of this group dance like puppets on a string.
I've gone QRV on this particular thread.
# "Ready to copy"?
# Or do you mean QRT?
Sitting here "ready to copy" on an interesting subject, and in the fuller
meaning of QRV, sitting here in the shack sending a string of v's on the bug
to show I'm ready.
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