Topband: K9AY "SWR" observations

K9AY k9ay at k9ay.com
Tue Dec 2 10:47:41 EST 2008


> Today just for fun I measured my K9AY system from the shack end of the 
> coax using an MFJ-259B...
>
> 73 Frank VO1HP
_______

Frank,

The K9AY Loop (and other terminated small loops) are non-resonant. SWR is 
largely irrelevant unless you have exceptionally long feedlines or you want 
to phase two or more identical antennas. The unit was designed for best 
match into 50 ohms, so the 1.6:1 you see at 1830 is no problem. You will not 
find a measurable degradation with 75 ohm line.

The "resonance" you see is simply the frequency where the matching 
transformer was designed to provide a reasonable impedance match. 
Interaction with nearby antennas will have only a minor effect on this 
measurement.

73, Gary
K9AY



More information about the Topband mailing list