Ok, it is decision time! To splurge for the 5/8th wave(40m)
tall Titanex vertical or go for the more modest Uni-Hat CTSVR,
(see Lew McCoy's review, Dec. 94 CQ). The CTSVR is a vertical
"folded dipole", 1/16 wave on 160; 1/8, 80 and 1/4 on 40. It is
31 feet tall with a 15 foot diameter capacitor hat at the top. Four
lines drop from the hat (but only a foot or so out from the center)
to form the folded dipole elements, if I understand what I am
reading in the info Ed Goodman has sent me. He says the
CTSVR is actually classified as a magnetic radiator, since it
produces a large "H" field as opposed to an electric "E" field.
Six 34 foot long radials are used under the top hat structure
(aluminum spokes with a circumfrential wire conductor
around) at the top of the 31 foot assembly. Ed says the
maximum current point is up at the top, rather than at
ground level as in the usual 1/4 wave vertical. Thus the
launch point is claimed as being 30 feet up, with an angle
of 10 to 12 degrees. Ed sends along an interesting set of
field strength measurments taken with a Potomac FIM 41
meter. Measurments were actually made at and with the
Los Alamos National Labs via some sort of Federal Small
Business assistance program, so presume the test data
is real! The concept of the capacity top hat is pretty well
discussed in the ARRL Antenna Book, 17th ed, pg 2-38 to
40. However, this discussion covers a straight vertical,
while the CTSVR is a folded dipole, thus much higher
radiation resistance for its height: in fact, 50 plus/minus
5 ohms is the claimed spec. Ed supplies some impressive
DX contacts by his various customers, including some
40 CW VK0IR QSO's. Most supplied info is on 160. I
must admit I am discouraged about 160 out here. I now
have a full 1/2 160 dipole, but low in height; only time I
hear much on 160 is contest times; then I hear a lot,
but don't get many responses! It is about 2400
miles from Kauai to the nearest 160 station outside
the state of Hawaii (of course I can hear KH6CC on
160 nearly every morning and evening of the Fall and
Winter, but he has a full height 1/4 wave 160 vertical
and 120 elevated, taught radials, all plenty long!). Jack,
on the Big Island, is only about 320 miles SE of my QTH.
I am really
more interested in good 80 and 40 performance. And thus,
back to the Titanex, V 160 E. This is a 5/8th wave vertical on 40;
5/8th wave radiators have been known "forever" by the
broadcast industry as the best for maximum FSM to
the horizon, at least that is what I have read. I guess that
means the Titanex is 2.5/8th wave on 80; have no idea what
that would do!! I have no tech info on the Titanex and from what
I gather from John Downing's, W2NA, post(Contest relfc.) of a
few days ago, it is all in the German language anyway. But it
is a bit over 85 feet tall (26 meters). That is the appealing part!
To operate on 160, however, requires another $500 external tuner,
at the Titanex base I presume.
A third choice might be the Hy-gain Hy-tower, a 51 foot high
vertical; actually sort of parallel 1/4 wave verticals with some
options for better loading on 80 and to get 160 also.
The CTSVR is the least expensive, $500 plus guy material and
shipping to Kauai, total about $730; the Hy-tower, $630 plus
shipping of probably $200 (ocean freight), or $830 or so total;
and the Titanex probably something like $1500 including air
freight to Kauai from Germany(extrapolating from W2NA's
post for price and air freight to Los Angeles).
So, what to do. Anyone of you have any strong thoughts
or opinions? I have bveen stewing over this vertical antenna
decision for several months now. I have the Hy-gain Hy-tower
manual, a lot of info from Ed Goodwin of Uni-Hat, and the few
posts about the Titanex. Plus have read the Antenna Book,
seen KH6CC's awsome set up. And I want to try the vertical
polarized antenna, but since I am going to be out hundresds of
dollars, and lots of labor hours, I want it all to produce the very
best possible performance, at least on 80 and 40, and, hey,
maybe something better than my 40 foot high, 250 foot long
160 dipole. I am "borrowing" some unused plantation land
behind us to get the needed length on 160.
Well enough, any thoughts? Could almost put up two,
phased CTSVR's for the cost of one Titanex, hmmmm.
But the phasing would only work on one of the bands, I
guess. Out here most of the rest of the world lies to
the North, so don't really need a 4-square. North-South
would be just fine.
73, Jim, KH7M
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