Question:
I would like to know how an antenna works so that I can build one to
replace the one on my stereo . I live in an adobe house and have bad reception.
Replies:
Basically an antenna is extremely simple - it is just a wire
that is intended to have its electrons moved back and forth
by any passing electromagnetic waves. If the wire is straight,
then an electromagnetic wave with a wavelength that is too
short (roughly, shorter than the wire's length) will move
the electrons approximately equally in both directions, and
the signal will be weakened from what it could have been
with a shorter antenna. Since most radio transmissions are local
(except for short wave, which is a whole other story) the E-M
waves are likely to be coming pretty much horizontal, so that
means the orientation of our hypothetical straight wire maakes
a difference. There are all sorts of improved designs over
a straight wire though
Arthur Smith
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