Topband: K9AY Loop Questions

Andrew Ikin andrew.ikin at btconnect.com
Fri Jan 7 08:24:18 EST 2022


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




More information about the Topband mailing list