Hi Matt
Isn't that effect present in any antenna (except maybe a vertical)?
If you put up a dipole, there are 2 main lobes and off the ends is a big
null. I just don't see any antenna that is going to be perfect. In
order to cover many directions with dipoles or fan dipoles, you are
going to have to put up 2 for each band at right angles to each other.
If I want an antenna to cover NE/SW, a dipole will do that, but will
have nulls NW/SE, (assuming it is high enough to have lobes and not
shooting straight up) so now I have to put up 2 antennas.
I still can't see any disadvantage to an 80 meter (or longer) dipole fed
with ladder or window line, except maybe a bit more noise on the ladder
line. Every antenna has advantages and disadvantages - you just have to
weigh them out.
I have an antenna that is about 190 feet long, up in a tree about 90
feet fed with window line. I also have an 80 meter elevated vertical
with the base at 6 feet with 5 radials. For 40 I have a full sized
delta loop in a tree up about 70 feet. The center fed antenna works
better in most cases than both of those antennas doing an A/B test, and
I can use it on 160, 80 and 40. But, I am not using a tuner with a
funky built-in balun to try and match the antenna.
I just don't think there is one perfect solution for just 1 antenna. 73
Tom W7WHY
On 5/4/2014 9:56 PM, Matt wrote:
As the frequency of operation increases from 1 to 2 antenna
wavelengths, 4 new narrow lobes appear at ~45-50 degree angles to the
main lobes and continue to grow while the main lobes continue to
narrow and ultimately disappear.
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