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Old April 27th 05, 05:34 AM
 
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No that is not what it is all about. Some here object to the term of TOA and
want strict adherence to the description in terms of "elevation angle".
This same subject came up a few months ago and went on for a long time.
Now we are at it again and allowing the discussion to supplant original
thoughts.
You can now see that somebody has inventing a statement
in straw man fashion and then using the lie as a truthful fact
for the basis of an illicit attack.
Anything goes
I'll wager if you look up the thread of a few months ago
on a TOA thread you will see contrary postings by the same persons
that are posting now, this purely for the sake of a continueing augument.
This group will never agree to anything other than all is known about
antennas
and will fight to the death if anybody alludes to anything that conflicts
with this.
It is for that reason the debate has been throttled and why TOA as shown in
some
computor programs is used as a diversionary tactic.

I give up !

The world is flat.
I will not disagree with that statement anymore
so that emotions can now settle down and I can live in peace

In addition:
All is really known about antennas since there is no evidence
of a scientific book that has been written about what is unknown
about antennas.

In addition :
I urge all newcomers to the hobby to accept the notion
that propagation can modify radiation immediately after emmission
from a radiating antenna , this being a consensus of viewa by noted
Gurus in the hobby

In addition
If a commercial computor program uses the term of TOA
then it is not to be trusted aince it is based around terms
that are known to be invalid and it must be left to the user
to determine how far this invalidity extends with respect
to results obtained. Many commercial programs use this
same term so it is a case of buyer beware.

Best regards
Art




"Fred W4JLE" wrote in message
...
Art, propagation does indeed determine the takeoff angle. Let's call that
pTOA. An antenna also has a design takeoff angle. We will call that aTOA.

I think you may be using the term applied to an antenna, Don't confuse it
with pTOA. two different animals with the same name.

" wrote in
message
news:zgube.16975$c24.6191@attbi_s72...
Richard,
You are at it again, avoiding the supply of corroberation to what you

say
is true.
Stick to the basic statement that you made, which from their silence, the
gurus concur
with.
Your statement was that:
propagation is what determines TOA
and I ask for confirmation of the correctness of that
statement from you in the nature of some written text.
The gurus obviously accept your statement as fact, but I do not.
Usually you refer to a text to back up your statement ,but this time you
haven't, winging it
and relying solely on the fact that the gurus agree with you.
Surely you or some guru can come up
with a written text that states that propagation is what determine TOA.!
That is what this group is all about where gurus debunk the untruths
and supply the real truths and not to let old wives tale dominate.
You also stated that you made the ":assumption" presumably
based on the "facts" stated above that the Curtain could be considered as
similar to the dipole
since propagation determines that they are the same. This is total junk

,in
its entirety,
unless you or the gurus can come up with a written text that confirmes

their
positions.
Art


"Richard Harrison" wrote in message
...
Art Unwin wrote:
"---may I go back to the "compared to a dipole" statement which Richard
keeps brushing off."

I accept a resonant dipole reference as a given.

It is true that the antenna under test and the reference dipole have
different radiation patterns. Our goal was to compare received signal
strengths at locations of interest.

The assumption was that on average, the propaqgation was nearly the
same
for the signals received from both transmitting antennas. Good or bad
propagation, the difference between the signals depended on gain in the
direction of the receiver as the transmitted power was the same to both
antennas no matter where it landed.

Kraus says on page 535 of his 3rd edition of "antennas":
"Suppose that we express the gain with respect to a single lambda/2
element as the reference antenna. Let the same power P be supplied to
this antenna. Then assuming no heat losses, the current Io is the sq rt
of the power divided by the resistance of the reference antenna.

In general, the gain in field intensity of an array over a reference
antenna is given by the ratio of the field intensity from the array to
the field intensity from the reference antenna when both are supplied
with the same power P."

Kraus` example was our intended case.

Our expectations were met and our contractors were paid.

Best regards, Richard Harrison, KB5WZI