[TowerTalk] Questions Please?

DavidC DavidC" <eDoc@netzero.net
Wed, 6 Oct 1999 10:29:42 -0400


> We may be into another  "Apples Vs Oranges" debate here
> > FORCE 12: C3, C3S, C3SS  versus Tennadyne: T-6, T-8 and T-10?
> If we're into similar boom length comparisons, it should be C3S Vs. T6,
and
> C3 Vs. T8. The T10 has a 24 foot boom

Aww, close enough!  ;-)   OK, let's just look at those four.  Fewer
variables
is always easier for me!

> > Expected Pattern (mounted at 65 feet above sandy soil in west-central
> > Florida
> Since Force 12's in CA, and Tennadyne's in TX, that may be tough to do
> (unless they just show you a computer pattern). Actually, that's a good
way
> for you to get a couple free antennas. Almost as good a way as having a
> DXpedition (hehehehehe) ;) ;)

You mean you doubt that they can estimate (or report field tests from
owners)
in an environment similar to mine?  Tennadyne specifies a minimum of 38 feet
above ground, I'm reasonably certain that they and Force 12 have a pretty
good
idea how their products will perform in my environment ... it isn't *all*
mystery.

I don't expect any free products, nice thought though.  Had the trade for
the
second 60 foot tower come though I would have had two equal height towers
within 75 feet of one another and could have offered to perform A-B tests.
Oh
well, there are many better equipped and better informed Hams who can do
that.

> > "Gain at 74' includes ground reflection gain and is the computed maximum
> >  forward gain of the antenna over real, average ground at a height of
74',
> > as compared to a dipole in free space.
> Which is going to cause a problem in comparisons unless Tennadyne has 74
> foot towers in the same sort of environment as Force 12.

I'm sure if they decide to do so they can discover a similar environment
where
they have, or easily may, test the beams side by side.  It's not a matter of
possibility
just one of will.  Perhaps K7LXC and friends could perform the tests?

> Since I suspect both antennas are going to be within a dB or 2 of each
> other, things like environment are really going to make a difference here.
> The advantages of one environment over the other just may be worth that 2
dB.

Ayuh.  We need to control for that variable to be sure.

> We need someone UNBIASED to make the comparisons in the SAME ENVIRONMENT
on
> the SAME TOWER, repeat them OVER TIME, against some sort of FIXED CONTROL
> and post it here.

I suggested in a private E-mail a week ago that perhaps we need a 24 hour
period where a
whole lot of Hams conduct a detailed set of tests with the many different
antennas.  That would
allow us to control for propagation and would provide some initial data from
which to further
narrow the parameters for a follow-up 24 hour test.  It would be fun and
informative ... the
contests begin to get tiresome sometimes, especially when they spam the
entirety of the bands.

73, DavidC  K1YP

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