O.K. Jim you have my respect so I will go over things again.
I commented that I always thought that it was impossible to have
max gain at the same frequency that one obtained max F/B F/R.
Presumably you read that.
I then stated a theoretical situation where elements worked in pairs but
equal and opposite except
the driven element
You read that I assume
So to draw a "polygon" of the array element phases and current we start with
the driven element,
a vertical line of scalar length and then move on to add a scaler length and
phase to the end of the
director "length.
Hopefully you are still with me
But remember I stated that all other elements were equal and opposite in a
twosome form
to another element, thus even tho we we have gone thru the normal routine we
still arrive at the end
of the driven element scalar line.
Hopefully you are still with me
So to close the scalar diagram we have a line that represents an element
that is in phase
with the director i.e additive. This diagram does not show that the element
pairs are doing
nothing and therefore of no use, those elements still radiate but they
oppose each other
with the final result that to close the diagram an element is required that
has the same
phase and magnitude as the fed element
Still with me I hope
With a single dipole over ground we get a figure 8 radiation pattern
but we have just shown how an array can be theoreticaly formed that
results in a unidirectional form where one part of the figure 8 pattern
has been cancelled and at the same time we have two radiation patterns
on the same side of the feed point in additive fashion in the form of a
perfect circle which is larger than either of the circles formed in the
figure 8
pattern.
Yes a lot of steps in this thought process but stick with me
Looking at the final large circle we can say that the demise of the rear
pattern
equates with maximum gain and where the lobe width has become larger
instead of the normal narrowing effect that we get with a Yagi
Still with me?
We can also see that using such an array can avoid the manufacture of side
lobes
whether they are frontal or otherwise as our "Polygon" is symetrical where
one
made for a yagi is not such that errant reflective rays are created.
To wrap things up: the thread was created because I had created such an
array
using NEC with 300 segments per half wave which produced awesome front to
rear figures which some readers questioned the feasability. I also
questioned the results
of the model for many months ,UNTIL I came up with the cited analogy
The model matched the analogy tho the pairs of elements were not exactly
equal
but very close and the resulting pattern matched the analogy in that it
became
LARGER. With two strikes in agreement I then sort for a final crunch mode
and that was
to make what is a mechanical difficult array to build as well as expensive
for something
that still had lingering questions. The winter has been harsh but with a
little time spent
each day during the last six months I now need one half day of good weather
without wind
to place this new fangled array at the tower top and without the need of the
heavy rotor
( prop pitch) which was needed for its equivalent long boom yagi.( I do this
without help
and I am not as strong as I used to be now that I am past 70)
I don't understand the derisve comments regarding my beliefs and the
ensueing
experimentation and building except there is a prevailing thought in the
U.S.
that it is impossible to discover anything new as every thing possible was
already
known, but else where in the world the average ham still experiments to
pursue
new knoweledge.
The world is really seen as out of step with the U.S. in more that one way
and this
thread portrays just one more thing to add to the list.
Regards
Art...... KB9MZ,,,,,, XG
\
I then illustrated where such an array could be drawn polygon fashion
You read that I assume
"Jim Kelley" wrote in message
...
wrote:
Yes I am aware of that and I expressed amazement at your lack of
knoweledge
as expressed in this thread. At the same time I see you are referring to
stuff
that you wrote when you were younger and things change as you get older.
A case in point is the ELZEC program which frankly does not match up with
todays technology or competitive programs yet maintains a high price
presumably based on your past achievements.
But when you express your knoweledge as you did this week
and showed complete lack of knoweledge regarding the subject at hand then
it may well be a sign of the times as it were and you resorted to attack,
not the
underpinnings of what I stated but me as an individual. If you were a
profesional
you would have attacked the polygon example given at the onset of this
thread
but then you expressed lack of knoweledge of the subject and I commended
you for that but the passing of time places no mercy on any of us
mortals as
we age despite our personally perceived station in life.
What you described would be at best be described in contemporary venacular
as a polyline. As has been explained, a polygon is a closed shape. A
polyline could form a polygon in the special case where the phase angles
sum to 360 and the line segments are of proper length and in a particular
order. I think most of us here know that Roy of all people has no trouble
at all with such a concept. I also have been following the thread, and
what you didn't describe is how any of that relates to the antenna
question you asked. Hence the mix-up.
73, ac6xg