Doug, I run a 3L SteppIR with the passive element on 6m. I had a stack of
modest sized yagis, and wished to consolidate. I'm a bit disappointed in the
SteppIR's performance on six in that I thought the forth passive element was
going to give me 4 element performance. I believe it does not, but rather that
of a 3 element 6m yagi which was what I took down. That are custom dimensional
revisions of the yagi that some say improves the performance on 6m, but I have
not attempted it yet. Of course, element revisions are very easy to do with
the antenna. The passive element is not necessary, but I've head performance
is dismal without it. Keep in mind that with if you add that passive element,
the 180 degree beam reversal mode (very handy on the HF bands) is rendered
unusable on 6m. I'm presently planning a second tower to transfer the SteppIR
to, whereupon I plan to put up a separate yagi for 6m, and make that a VHF/UHF
tower only.
Tom Hybiske, K3GM
--- On Sun, 9/6/09, Doug Rehman <doug@k4ac.com> wrote:
From: Doug Rehman <doug@k4ac.com>
Subject: [VHFcontesting] SteppIR's on 6m
To: vhfcontesting@contesting.com
Date: Sunday, September 6, 2009, 9:49 PM
Is anyone using a SteppIR antenna for contesting on 6m?
In order to add microwave bands to the tower, I need to consolidate some
antennas. I've got an 8 element Cushcraft log periodic for 20-10, a
Cushcraft D-40 rotatable dipole for 40, and a 5 element 6 meter beam that
I'm contemplating replacing by a single SteppIR. This is predicated upon
being able to get at least ballpark equivalent performance on 6 meters (as I
work VHF/UHF contests, I can't give up much on 6).
The antenna will be mounted at about 55' (where the log is now).
The SteppIR contenders are (all with the optional 6m passive kit):
1) DB-18 ($2,550 + $82/6m = $2,632)
2) 4 element ($2,285 + $375/40m + $164/6m = $2,824)
3) 3 element ($1,519 + $375/40m + $82/6m = $1976)
Since I don't work much 30m, I don't see the DB-18E as an option (the only
thing I see different on the E is an additional element on 30m for $400).
Comparing the gain figures (since it's gain figures from the same
manufacturer, I'd hope they compare...):
The DB-18 beats the 3/4 element by 4.4 dB on forty meters and 3.3 dB on 30m
(2 elements on 40m/30m versus a dipole).
The DB-18 and the 3 element are identical on every other band (20-6m).
The 4 element beats the DB-18 and 3 element by 1.6-2.1 db on 20-10m and 2.9
dB on 6 meters.
One thing I did notice about all three antennas is that the F/B is only 11
dB on 10m.
While I like the performance of the 4 element on 6m, the boom length (32')
is somewhat problematic. The tower is a Tri-Ex LM354-HDSP that pivots over
at about 8'. A 20' or shorter boom allows for me to lay the tower over to
work on the antennas along the 24' boom. The 32' boom would require me to
partially disassemble the boom before bringing the tower completely
horizontal.
For the $600+ difference between the DB-18 and the 3 element, plus cutting 2
sqft of wind load, the 3 element is looking like the winner- but the extra
4.4 dB on 40m is tempting.
Someday I'll get the 100' tower up in the pasture; when I do, I'll reassess
what to put on it. In the mean time, I need something that will be
comparable to my current 40-6m setup.
Thoughts from those using SteppIR's, especially performance on 6 meters???
Thanks,
Doug
K4AC
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