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Old March 27th 05, 09:03 PM
 
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"Richard Fry" wrote in message
...
wrote:
As gain increases with a yagi design the forward
lobe narrows. So to the gurus of this group, what
actualy creates the narrowing of the forward lobes ?

______________________

A good analogy that needs no math to understand is that of squeezing an
inflated balloon from its normally spherical shape into whatever shape is
more appropriate for the application. There is a given volume of air in
that balloon. If you want the surface of the balloon to extend further
from the origin of its original sphere, the new shape must be narrower in
one or more planes than the original shape.

The shape changes can come from squeezing the balloon (pattern)
horizontally, vertically, or in combination -- which, in antenna hardware
is accomplished by an appropriate array of, and feed system for, its
radiating elements.


Right..... so what creats it, this "squeezing" that you talk about and from
where
does this "squeezing force come from in an "appropiate"array?
That's what I was asking not a discussion of what the
Yagi array produces. Why does the lobe narrow?
Art




RF