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Old October 17th 03, 01:18 AM
Tom Bruhns
 
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Cecil Moore wrote in message ...
Tom Bruhns wrote:
If you measure the voltage drop along the wire, it's essentially zero,
so along the wire the voltage between the end points of the dipole is
essentially the same as the voltage across the feedpoint.


Brain fart?


Just so we're clear on this, no, certainly not.

If you care why, consider the direction of the electric field adjacent
to the conductor, and integrate the component of that field parallel
to the conductor along the path of the conductor. You will in general
get a different answer than if you integrate along a path from the tip
of the antenna, out say a quarter wavelength, then parallel to the
antenna for a half wave, then back to the other end of the antenna.
There is no such thing as "the voltage" between the ends of your
excited dipole at an instant in time. There are infinitely many
potentials, as there are infinitely many paths you can follow through
the (time-varying) magnetic field.

Cheers,
Tom