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Old December 20th 07, 05:03 PM posted to rec.radio.amateur.antenna
art art is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 1,188
Default The pursuit of the all band antenna

It can be seen that a fixed radfiator hasd a primary frequency and
then some harmonic frequencies.
The spacing and the resonant points of an antenna resides in the
amount of resistance in the cuircuit
from zero upto a critical point as with a tank circuit. This
resistance value has the action of bringing the radiator
vibrational amplitude to zero where it then takes of to a diminishing
value compared to other componenents in the circuit to the point that
where the radiator is resonant the contained resistance has negnigable
effect.
Thus one can make a folded dipole with a variable resistance in the
radfiating circuit such that the main resonant point can be determined
as well as the spacing between the harmonic frequencies.
In addition, if the radiator consists of increased induntance designs
such as contra windings then the distance between the resonance point
and the harmonic points begin to decrease.
Thus using the above one can now make a all band antenna where the
resonance points line up with the desired frequencies.
An easy way to accomplish this is to wind wire on a dielectris from
end to end and back again several times
until one has wound at least two wave lengths on the former and then
feeding the arrangement at the beginning and ending wire points. Using
a mfj 259 one can then determine the spacings of the resonant point by
stretching the windins as well as adding the required variable
resister. Note. the resistance absorbs the energy between
resonance points and diminishes in effect as the point of resonance is
aproached. For more understanding of the radiation format of radiators
review the circumstances of voltage overshoot with respect to tank
circuits
The above will provide an alternate discussion thread that will take
away the current tunnel vision aproach
with respect to "black boxes" and bring the newsgroup back to the
advancement of antenna techniques if it is that that peeks one's
interests.

By the way, it is the ELECTROMAGNETIC field that launches the
particles from the radiating surface and it is the MECHANICAL REACTIVE
FORCE that provides the mechanical resonance of the radiator WHICH
JOINS THE THEORIES OF NEWTON AND . MAXWELL that Einstein struggled for
in vain.
For those that feel that mechanical laws of Newton cannot be used with
respech to electrical subjects( ala Roy) here is a chance for you to
prove your point.
Regards
Art Unwin, a limey no less
 
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