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Old October 30th 14, 01:28 PM posted to rec.radio.amateur.antenna
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Posts: 137
Default short antennae

On 30/10/14 08:47, Ian Jackson wrote:
In message , Frank Turner-Smith G3VKI
writes
In a full wave dipole the voltage at both ends will always be in phase,


Are you sure? Think on't!

so I would expect to see a very high impedance at the feed point.


Correct.

As you point out, matching the full-wave could be difficult and very
lossy.


Double zepp?

OK, what did I miss? In a full wave dipole, at the instant the voltage
at one end is peak positive, the voltage at the other end will also be
peak positive. Similarly, at the feed point, both legs would be at peak
negative and no current would flow in the feeder, hence the high
impedance. There would be a current flowing in each leg of the dipole,
but the currents would be in anti-phase. Where have I got it wrong? Do I
need another drink?

--
;-)
..
73 de Frank Turner-Smith G3VKI - mine's a pint.
..
http://turner-smith.co.uk
..
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