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Old April 28th 05, 07:46 PM
Richard Harrison
 
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Richard Fry wrote:
"The elements (bays) in these arrays all are one wavelength apart, and
driven with equal power and phase.

# Elements C-pol Gain (dBd)
1 -3.55
2 -0.21
4 3.09
8 6.34"

Bailey`s Table 10-I, which Richard Clark referred to as "naive", appears
on page 484 of "TV and Other Receiving Antennas".
The heading is Array Gain (approximate rule).

Nunber( of Half-Wave Rods (N) and
Numeric PowerRatio Gain (dB) 1
0
2 3
4 6
8 9

First difference from Richard Fry`s table is the loss of 3.55 dB as the
result of circular polarization (mostly) as half of the power which a
linearly polarized reference dipole would
use is cross-polarized.

The steps between doubling the number of elements in Richard Fry`s table
are all nearly 3 dB. Bailey says "approximate rule". He is vindicated.

Best regards, Richard Harrison, KB5WZI