When an inverted V gets long with respect to wavelenth, the main lobe
elevates pretty dramatically, so you no longer get a decent take off
angle...lots of radiation at high angles, but very poor at the lower angles.

I found this precise problem when trying to run inverted vee's as extended
double zepps...they don't work very well compared to the same antenna as a
flat top.

All I had to do was model the V using EZNEC, and sure enough a 3D display of
the pattern showed the problem. The nice gain lobes I was looking for were
missing in the 2D display at the elevation angles I had expected. Going 3D
showed me where they went...way high, not very useful for what I wanted.

The moral of the story: if you want long (w/r to wavelength) dipoles to be
effective at low angles, only use flat top configuration. Inverted V's don't
do well as they get long with respect to wavelength.
"Rick (W-A-one-R-K-T)" wrote in message
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I just put up an inverted V that is up about 70 feet in the center and
about 15 feet at the ends. Each leg is about 130 feet long, or about 260
feet overall, which is right around a half wave for 160 meters. It is fed
with ladder line and an LDG auto-tuner.

I also have a dipole antenna that's up about 17 feet and is a half wave
for certain MARS / CAP frequencies above the 75 meter band, hence it's a
bit short for 75 meters. That antenna is coax fed and goes through a
different LDG auto-tuner which allows me to use it on 75/80 meters with a
good match.

The long and high inverted V doesn't work any better than the short and
low dipole, and in some cases doesn't work as well.

I have checked all the connections on the inverted V and even did a
continuity check from each side of the ladder line, up through the feed
point, out each leg to the end of each leg, and all seems OK.

I have tried switching auto-tuners (taking the one that's on the coax-fed
dipole and putting it on the inverted V) with no discernible difference.

Seems very strange. Any ideas that might account for why the V doesn't
work better?