Shunt fed vertical?
Since things are a little slow here...
As I continue to experiment with my 28 foot vertical I attempted to
try a shunt feed today. It totally escapes me how I might model it
with EZNEC 4 but I do have an MFJ-269 to work with.
I set up the radials and tied them to the base of the vertical. I
moved up the vertical from the bottom 55 inches. No real reason, that
is the length of wire I had handy I fed the wire with the MFJ 269 with
the coax shield on the ground side.
What I expected to see was some thing resonant between 6-8 mhz with a
lot of reactance and who knows resistance. It did not happen....
What I did see was a resonance at 23 mhz with Rs= 48 and Xs=5 for a
1.1 SWR!
Dabbling with EZNEC seems to suggest there may be something happening
like a 5/8 wave radiator but many factors had to be forced into place.
So that leads to my question: How do you shunt feed a 28 foot
vertical?
John Ferrell W8CCW
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