Gaussian cluster antenna array data
Richard Clark, KB7QHC wrote:
"Having a reference is always the point to start from."
Kraus compares his W8JK array with its two dipoles spaced only
1/8-wavelength apart, against an array with its two dipoles spaced
1/2-wavelength, one dipole above the other. These two arrays are both
pictured on page 184 of the 3rd edition of Kraus` "Antennas". Though the
gain of either array is about 6 dB, the inherent impedance of the W8JK
array is low due to its close spacing and coupling. Impedance of the
1/2-wave-spaced array is 333 ohms at its drivepoint. Impedance of the
W8JK is adjusted with a stub to match the feedline. Its inherent low
impedance may cost the W8JK about a fraction of a dB in efficiency (see
page 187) but as both dipoles are high (sharing the same horizontal
plane) a lowered angle of maximum radiation has proved advantageous for
the W8JK.
Kraus` comparison seems fair and his disclosure seems complete. Maybe
that`s why the the antenna array known by his amateur radio call sign is
famous.
Best regards, Richard Harrison, KB5WZI
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