I have finally concluded that the only way I'm going to get on 160 is to
shunt feed my tower -- 100ft of Rohn 25 with a Force 12 C4 on top.
Resonant antennas (inverted vees, slopers, etc.) all seem (from modeling)
to screw up the pattern of the 80-meter lazy-vee array. The electrical
length of my tower plus beam appears to be in the range of 110-130 degrees,
so my assumption is that it won't bother the 80-meter array any more than
it does now, even with the shunt feed structure (aluminum hardline) and the
short feedline open when on other bands.
Is that assumption correct?
I'm hoping to avoid an extensive array of buried radials. Am I correct in
thinking that I can use 4 elevated radials with the shunt fed tower and get
decent current return? If so, is the height above ground important
(provided it's more than 1.1 deer high) and should the radial conductors be
connected to the tower right at ground level, or ??? I would think that 8
feet above ground (for example) would not be at ground potential at 1.8
mhz, even though the length of tower below that is small. I really feel
dumb about this last question, but realize that my knowledge of antenna
theory falls short when it comes to verticals (in particular).
73,
Pete N4ZR
In Wild Wonderful, fairly rare WEST Virginia
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