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Old February 21st 04, 07:04 PM
Jimmy
 
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"Art Unwin KB9MZ" wrote in message
m...
Tom,I agree with much of what you say but the problem goes much deeper
than that, and much of the blame rests with academics taught.
Let us look at what is called by some as a 'simple dipole'.
The dipole is very inefficient radiator.
The only claim that you can place on it is that it is has a low
impedance
at resonance...Period. There is no calculation available in any of the
touted books that maximum gain per unit length is design related to a
dipole! The dipole is only a reference that other antennas can be
related to even tho it is a very inefficient radiator per unit length.
Over time academics have made the dipole as something very efficient
about which every advance must be related .
That Tom is very incorrect and it is that which is what prevents the
emergence of new ideas that push the envelope. If one just spouts what
is in present day books then they are just followers that suck up the
dipole aproach which thus prevents them from contributing anything
that pushes out the envelope. Education
can only take you so far and it is dependent on those who have
received an education to push the envelope further. If one doesn't do
this then they are just quoting things that were told to them or they
read in some book and thus are not equiped to pushing the envelope.
Until the simple dipole is shead of its illusionary powers by the
academics who write the books newcomers can only copy, and not
progress. Ofcourse, academics who just memorise can still attack
people, those who do not agree with them, in a personal way in the
hope that a raucous crowd of peasants will echo the academics trash
around the Gillotine.

Regards
Art





Gain and efficecey have nothing to do with each other

Efficency is based on how much of your signal your antenna turns into heat
compared to the amount radiated and nothing more. Gain is based of how your
antenna shapes the pattern. The fact is a simple dipole will often service
more area than high gain antennas. The high gain antenna just uses radiation
that would normally go some where you are not interested in to intensifies
the signal in an area where you want to communicate. Art this is a fact you
really need to understand. Dont feel bad about it though, I believe gain was
a very poor word chosen to discribe the effect of an antenna on the shape of
its field. Gain typically means to amplify which is something an antenna can
not do. This all means that it is possible that a simple dipole is more
efficent than a Yagi_Uda antenna with 10 dbd of gain. The dipole may be
slighly more effeicent due to less losses coupling to the feed line. Mind
you this will be a very small diference in losses when comparing well
designed antennas.

Unless you are willing to give demonstrative proof of your ideas you should
not insult us that that hold dear our beliefs and theories by refering to us
as raucous crowd of peasants. I you are unwilling to prove your points you
only appear as a fool. Our belefs and theories have been tested over many
years and have found to be true as far as they have been tested, your ideas
have not been tested by you at all. You assign words new meanings that are
not typical of those discussing antennas and expect others to understand
you. You ask for critical opinon of your ideaas but become angry when
someone disagrees with you. If you really think you have some kind of new
break through put your money where yiur mouth is and demonstrate them or go
join the free power bunch, they will love and embrace you and take your
money..