Loop antenna question????
Greetings!
I picked up 2 Alford loop antennas from a ham fest. The antenna(s)
is for 112 mhz The data plate states VOR antenna 50 ohms. The
antenna(s) has Three N connectors one is to feed the RF from the
transmitter the other two are connected with a 31.5 inch length of
RG-214 coax. ( the 31.5 inch coax came with the loops)
I looked in the ARRL antenna hand book and it looks like the loop of
coax is configured as a 4 to 1 step up Balun??? The ARRL hand
book states that the Coax loop should be a electrical half wave of
coax : The coax loop is about 5 inches short of 1/2 wave at 112 mhz
When I hook up my MFJ-269 I get the following:
Freq: 112 mhz
RS - 9
XS - 68
Impedance : 95 ohms
VSWR 14.8 ????????
both loops have about the same readings!
WHY??? They are stamped with 50 ohms ?? but they don't measure out
to the data plate??
Can the length of the Balun loop have effect on the VSWR of the loops
What do the MFJ-269 readings tell you
Thanks!!!!!
Dave
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