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Old April 25th 05, 10:34 PM
Richard Harrison
 
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Art Unwin wrote:
"My point is that again figure alone is meaningless unless the elevation
angle differences or perhaps a 3 dB window comparison are also
supplied."

Reg knows very well that a quantity is determined by comparing it with a
known standard.

The power gain of a resonant dipole in free-space is given by Terman on
page 871 of his 1955 edition as 1.64.

Kraus agrees on page 54 of his 1950 edition and converts Terman`s power
gain of 1.64 to 2.14 dB (referenced to an isotropic).

The values given by Terman and Kraus are accepted.

Horizontal antennas at the same heights tend to have similar elevation
angles, but even if they didn`t, comparison of the signals our two
antennas laid on the target represented our interest in the matter.

What we confirmed was that the new curtain antenna had a gain comparable
with our rhombics but over a wider beamwidth which meant listeners on
the edges of our coverage got a better signal with the new curtain
antenna.

The bandwidth was less than a phombic so the curtain meant more work for
the operators, but the broadcasts were for the listeners` benefit.

Signal strengths were measured at many locations around the target area
to define the coverage of the antenna pattern.

Best regards, Richard Harrison, KB5WZI