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Old February 5th 04, 02:43 AM
Art Unwin KB9MZ
 
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O.K. I have downloaded the file
Since the dipole is resonant the current magnitudes
on either side of the center must be symetrical.
If you had a half wave length of wire between the end half waves you would
have a half wave ofcurrent with a negative phase which reflects a phase
change at half wave intervals. every thing so far appears O.K.
Now you aparently changed the wire length so that half is represented by an
inductance and the remaining portion
stays in linear form to where a phase change occurs again.
Now the problem part. In another drawing reflecting a vertical the insertion
of an inductance was inserted
suddenly created an immmediate phase change even tho its wire make up only
consisted of something less than a half wave length on a predetermined basis
that any inductance initiates a phase change at both the beginning and the
end which I read as false.The phase change is predicated in a way by the
wire length that was crunched up to form an inductance.but without
capacitive coupling of any sort which is impossible.
When looking at Moxons book he shows two dipoles in linear form with a
parallel circuit at the center which can
represent a loop of a half wave dimension. He also shows the cureent flow in
the system from the left to the right
until it intersects the parallel loop circuit where it receives current that
is flowing counter clockwise within the loop.
At the end of the loop the current changes to one that symetry demands i.e
current is zero following a sinosoidal shape such that it reaches zero
current at the end as symetry requires for a resonant array...
Fron Moxons drawing the loop is simulating a mechanical pump operated by the
direction of current flow at any particular time where the input and output
current are one and the same value so that symetry required for resonance is
obtained.
Now when I come to your drawing of a vertical I become confused because the
top end is clearly zero current flow
which presumably is a requirement for resonance
but the inductance suddenly becomes dimension less
even tho it must have dimensions to reflect phase change
thus the current flow assigned to your vertical is clearly flawed.
Now Cecil I am not skilled in the art of antennas or modeling as you are but
I probably reflect the thinking
of the average ham. Thus I would not treat it personaly
if you viewed my reasoning as one that reflects a novice.
So why not correct the above reasoning in order given
so that the average novice can advance in the art
because of an enlightning rebuttal..
If we are beyond education such that we cannot be helped without duplication
of your own experiences then so be it and we must agree to disagree.
As I said earlier nothing personal but I would like the benefit of your
enlitenment so I can rebuild on a firmer foundation.
Regards
Art