Walt
I said that both antennas are beams. What I was addressing was the
height portion of the question whereas tho they are both beams the
effective height measurements were different.
i.e Planar beam versus other beams where the quad is not a planar beam.
Seems like effective height measurements contribute to most yagi /quad
comparison debates. There is also another side of the coin when
measuring effective ht and that is when a yagi is positioned vertically
where it is still planar when comparing to a quad element moved thru 90
degrees.which is now planar. If you chose to answer the posting what
part of my posting would you leave out, or question its veracity
especially after reading the total thread?
Regards
Art





Walter Maxwell wrote:
On 15 Oct 2006 21:35:43 -0700, "art" wrote:

Yes there is a difference, A yagi is a planar beam ie on a single plane
so the height of the array is the same for all elements in the array
which creates a major lobe or beam.
If the array is not planar such as a Quad then the elements are at
different heights
so the true or effective height of a quad antenna which is also a beam
style antenna is approximately the center point of the array or
somewhere between the top and bottom of the quad element.
The point to stand by is that the height of the feed point is
immaterial with respect to the effective height of an array. In another
post I pointed out that no matter which element is fed in a array the
effective height of the array is always the same and thus the TOA is
always the same
Regards
Art

Hi Art,

One of the most demeaning aspects of this newsgroups concerns misunderstandings
of definitions and terminology that often leasd to unfortunate and unnecessary
arguments.

To wit: Yagi vs beam.

It's been my understanding that any combination of radiating elements intended
to radiate more energy in one direction than omni establishes a major lobe that
is called a beam. In other words, any directional system establishes a beam.
Therefore, 'beam' is generic to all directional radiators.
It then follows that 'Yagi', 'quad', 'W8JK', 'EDZ', are all 'beams' of a
particular type or configuration.
XXXXXXXXXXXXXXXXXXXXXXXXXXX
I agree, where did I say different?
XXXXXXXXXXXXXXXXXXXXXXXXXXX

I believe it's important that correct terminology be used for the benefit of the
newcomers--would you not agree?


Yes I would agree but if one is unsure of the true terminology should
we ban all from ham radio as it has now moved from a hobby to.......
IEEE transactions on antennas ?
I believe everyone has become too picky as to who is a ham and who is
not and thus are becoming adverserial to those not fully versed in the
art. Look at the long posting regarding
antenna efficiency where everybody jumped on the electrical version of
efficiency ie transfer of electrical energy to a time variant field and
totaly ignoring the reference to pattern volume.with respect to the
main lobe portion. How on earth do electrical engineers chose
iapliances for the home when so much device energy is wasted or does
not imprint on the required use?
The majority of people on this newsgroup including newcomers are now
convinced that energy entering an array is nearly equal to the
radiation energy contained in the single main lobe and they contest
other thoughts by the use of " ratios": which is devoid of units and
relavence. Even if they didn't want to read the posting as a whole not
one looked at radiation efficiency change when viewing radiation from a
complex circuitry direction or in other words driven elements in
parallel since elements in parallel alter the resistance DC to
resistance radiation ratio ,admittedly small but there none the less. I
would admit to a review of antenna efficiency or radiator efficiency if
it was normal for radiators to be made of wood As I said earlier to
much nittpicking going on such that hams are becoming adverserial to
each other and that is to bad if we want newcomers to stay around.NUFF
SED
Art



Walt, W2DU