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Old April 26th 05, 10:00 PM
 
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O.K. Richard I'll leave it at that with you . You continue to send
prewritten responses to questions that were not asked.or do not pertain to
the subject at hand
I will leave it to you to alert all antenna labs not to test antennas when
there is no
propagation or, failing that, leave a bucket under the antenna to compensate
for the lack of TOA
or elevation angle because of the lack of propagation generated modifying
actions..
I don't know that if they leave the door open during testing it will
suffice.
You can always supply a written technical text to justify youir actions when
you find it.
Nuf said
Art


"Richard Harrison" wrote in message
...
Art Unwin wrote:
"Surely you or some guru can come up with written text that states that
propagation is what determines TOA."

I don`t find TOA in any index. I find "elevation angle", which I suppose
is a synonym, in my 19th edition of The ARRL Antenna Book. On page 2-9
it says:
"The elevation angle is referenced to the horizon at the earth`s surface
, where the elevation angle is 0-degrees."

On page 3-5, the same book says:
"Now look at Fig. 4A, which compares the computed vertical-angle
response for two half-wave dipoles at 14 MHz."

The Antenna Book is not very definitive.

"Transmission Lines, Antennas, and Wave Guides" on page 314 says:
In order to escape from the earth without excessive ground attenuation,
a sky wave must leave the earth at an angle of at least 3-degrees above
the horizon.---At 3-degrees elevation, the distance per hop is about
3,500 km (2,100 miles). Longer distances are automatically broken up
into units not exceeding 3.500 knm."

It`s the medium breaking up the hops, not the antenna.

Best regards, Richard Harrison, KB5WZI