N4IS, Wrote on Jan. 7. " I’m afraid your information is not accurate, SAL
is the same as a K9AY, the two wires close to each other can be removed
because they cancel each other. The remain wires works like two vertical in
phase, as the same in any flag, loaded loop or pennant. The cardioid pattern
is the same."
Jose,
The SAL is a very close spaced phased array of two loop antennas, hence, it
has high rejection of the Electric Field in the antennas near field at MF.
The K9AY is a combination of a H and E field antenna, that generates its
cardioid pattern by combining the two fields using the termination resistor
to reduce the phase and amplitude difference between these fields. Hence,
the K9AY and other similar antennas like the FLAG are prone to pattern
distortion if nearby objects are within the antennas near-field.
The SAL has different pattern compared to the K9AY.
Early editions of Keens Wireless Direction Finding describe and two turn
cardioid loop with a ground connexion in a similar fashion to the K9AY.
73
Andrew Ikin
G8LUG
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