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Old February 20th 04, 09:45 PM
aunwin
 
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"Dave Shrader" wrote in message
news:%huZb.24701$Xp.104370@attbi_s54...
Art, did you intend to compare a 'CLOUD WARMER' against an 'OVER THE
HORIZON' class of antenna? Isn't that apples and oranges?


No it is not, both have gain.It is just that the maximum gain is at
different angles both vertically and horizontally.Extra gain in an undesired
direction is just plain useless.
There is absolutely no reason why a rotatable antenna cannot beat a standard
beverage depending where your interest are. If your interests are ambiguos
then so will be your comparison responses , something I am sure you
understand.

BTW, who limits Beverages to received ONLY? There are some very long
Beverages in VK land for long haul low band DX.


I will give you that but in general they are used for listening but that
was not the message I was trying to supply, Cecil supplied simple dipole
gain as stated by EZNEC so I had the computor supply a 'better' antenna but
what does it really mean. Suppliers of computor programs state if it does
not look real then it is not! So the simple statement of gain is meaningless
if it is directed at not acceptable areas which is why I pointed to
ambiguety. Now for my actual antenna which is rotatable on 160, what is the
gain at 90 degrees which you label as NVIS would be acceptable if the
computor supplied it to you ?
If given the the gain at 90 degrees would you interpret that as having zero
over the horizon at say 15 degrees ?. Zero at 30 degrees? I would say that
if an antenna is a cloud warmer it does not necessarily discriminate against
low angle signals so it is not or should not be a statement of derisement.
Frankly this business of comparing antennas is pretty stupid UNLESS one
prescribes a specific object . Cecil gave such a comparison but did not
reveal that in many directions his antenna was just plain deaf. Good for
confusion or for an ensuing augument but other than that it had no value.
I would also add that if a computor gives you a surprising figure then you
must have a second opinion or make one. To do anything else is to admit all
is known and figures of merit are known for every shape and size and are
printed in books so one can learn what is not real when shown on a monitor.
Were you not ever surprised during your years on the range at what your
equipment revealed? Did you ever compare antennas where one had more gain
than the other but proved to be actually deaf in some directions ? I am
quite sure that during your working career any statements you made with
regard to antennas was specific and to the point and devoid of vague
statements which were not pertinent to the assignment given. If it wasn't
then your career was short.
Nothing personal intended above I was just trying to make a point with Cecil
to whom I addressed the posting but I welcome your remarks.
Regards
Art
..
aunwin wrote:
SNIP

So I just designed an antenna with a computor program for 160 metres

based
around a patent write up of mine which probably will not be issued

until
sometime next year.
The beam is rotatable and is at a height of
20 metres. The max gain is 7.35 dbi at 87degrees. Minimum gain at this

TOA
is a few db less. Compared to another antenna, and that is what you are
doing, the gain exceeds a Beverage at any angle over 10 degrees even if

the
beverage was rotatable.
Unlike the Beverage the antenna can be used for transmitting.


SNIP