Brian & Guys,
There are plenty of reasons for one antenna
seeming to outperform another.
I'd like to suggest that :
1) You can't get something for nothing. Another
way of saying this is that you can't do better
than theory says. You can do a lot worse. If you
don't accept this, then you believe in perpetual
motion machines.
Theory says log periodic antennas optimized for
bandwidth/swr with the same boom length will at
best be equal to optimized yagis at a given
frequency.
2) Log periods are not chosen for gain. The are
chosen for bandwidth.
Per pound, foot of boom length, $ or anything
else, they are theoretically and demonstrated to
be worse than antennas designed for and optimized
for narrower bandwidths. See 1. You've traded
gain for bandwidth. If you don't believe this,
try using AO or some antenna design program see if
you can come up with a super bandwidth antenna
(for the same boom length and number of elements)
which has more gain than one designed for a narrow
bandwidth. Good luck.
3) If the T10 were tested head-to-head with some
of the antennas mentioned, in test range
conditions, they would probably be worse in a gain
sense. If there were any benefit at all, it would
be small (1 to 2 db). The benefit, if any, would
probably be due to boom length-- not the the
"superiority" of log periodic antennas for gain.
In closing, I'd like to agree that any antenna may
outperform any other antenna if the conditions are
right for it. We've all heard stories of
tribanders at 50' outperforming big arrays at
100+'. It happens on 10 meters all the time when
conditions permit. However, height (getting the
right angle of radiation), not antenna design or
antenna gain that is the reason.
Relying an innuendo and personal endorsements may
"feel good" but "you can't fool mother nature".
In the end, it's your money to spend. I simply
prefer to spend mine based upon what theory
indicates.
73 de Brian/K3KO
Brian Hemmis wrote:
>
> Agreed ! My T-10 is going into its 3rd winter here on the Great Lakes.
> Bought mine based on recommendation by Big Gun Matt KC1XX who does antenna
> installs. He recommended this antenna to the Harvard Wireless Club W1AF when
> they were forced to take down their Telrex Christmas Tree array. I've had
> other "gain" antennas to compare it to as well as DX King K3TUP abt 2mi away
> to mix it up with in pile-ups and contests. 2 thumbs up on this one ! Brian
> K3USC/ W3DXR
>
> Subject: [TowerTalk] Tennadyne
>
> >
> > To those who are interested,
> > I have a T 10 Tennadyne. It has been in the air about 11/2 years and I
> > will report that the performance is outstanding.....
>
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