Also, does anyone have
> any idea why
> signals received on my inverted vee (apex at about 40 feet and
> ends at about 15
> feet) would consistently be 3-6 db greater than on the vertical?
I have done extensive A/B comparisons between inverted vees at
various heights and verticals on 40 meters. For DX signals,
such as foreign broadcasters, inverted vee height has negligible
effect between 30 ft and 90 ft. Also, a full size 1/4 wave
vertical over a huge ground screen is equivalent to the vees
for DX. Perhaps your Sigma 40 is simply 3 to 6 dB down from
a full size vertical with ground screen. I wouldn't be surprised
it if was that much less efficient, especially in an urban area.
On signals within a few hundred miles, the vertical has a null
at high angles and the vee's have ground gain. I have seen
a vee at 30 ft beat a vertical by 30 dB on a calibrated S meter
for stations 50 to 100 miles away.
Since you have the room for an inverted vee, you should probably
just use it and forget about verticals. You need to keep the
inverted vee up for receive purposes anyway. I never use a
omni vertical for receive now that I have a vee up. I only use verticals
on 40 now in the context of a 7 element phased array and then only
at distances of more than a few 100 miles. Otherwise, I would
use my inverted vee at 60 feet all the time.
As always, YMMV.
Rick N6RK
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