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Old July 21st 03, 05:58 PM
Richard Harrison
 
Posts: n/a
Default basic question about radio waves !!!!

Nic Santeen wrote:
"The RF source applied to a dipole generates a magnetic field and
electric field 90 degrees out of phase (it is a capacitive antenna)."

It could be an inductive antenna or a resonant (resistive) antenna, and
the radiation fields, E&H, would still be at right angles in space, in
the plane of the plane wave, perpendicular to each other and to the
direction of travel.

Static fields distant from a current-carryinng wire are in a small way
analogous. Imagine the current flowing toward you. Electric lines
radiate like spokes radially positioned around the wire. Magnetic lines
are concentric and make circles around the wire. At great diatance from
the wire, the magnetic and electric lines are practically perpendicular
and they are both perpendiicular to the direction of energy flow. Don`t
make too much of this analogy, but it may be illustrative.

Borrow a copy of Terman`s 1955 edition from a library and study page No.
1.

BNest regards, Richard Harrison, KB5WZI