The following are preliminary impressions only. I have some interaction
problems that invalidate any quantitative results to date. Nonetheless, ...
I put up a 3el SteppIR last month. It went together beautifully.
Materials and documentation are first class. The only assembly problem
was a marginal supply of the self-fusing tape that you use to seal the
fiberglass section overlaps. They sent me another spool and promised to
increase the allowance in future manufacturing. I was in a hurry and
didn't want to wait, so I scrimped the last few joints and one will
probably have to be re-taped the next time I take it down, hopefully not
for a long time. FluidMotion assured me that even an untaped joint is
highly unlikely to come loose.
Having gain on 17 and 12 for the first time is wonderful. The 180degree
reversal feature is amazing - 4 or even 5 S units difference on some
paths. I enjoy using it to switch between JA and Caribbean although it
takes a few precious seconds during which you should not transmit with
high power; annoying in a contest. The bidirectional feature hasn't done
anything for me yet and seems to have higher SWR than the unidirectional
modes. But see below.
But none of the above is why I bought the antenna. I wanted a good basic
tribander with low SWR across 10, 15 and 20. I got that on 20 for sure.
I used it in the CQP this month and it felt at least as good as my C4S
on 20. Of course, with twice the boom length, it certainly should! SWR
is good across the entire band. On 15 and 10 I did not feel even
relatively loud. (From this location, the little C4S actually does feel
loud, but it was down and unavailable for direct comparison. Conditions
during CQP were mediocre.) SWR was also on the high side - 1.4 to 1.8. I
believe I have an interaction problem with an 80m rotatable dipole about
two meters below the SteppIR. I can see this in SWR changes on the
dipole when I adjust the SteppIR. I had ignored Force 12's good advice
to mount that dipole at ninety degrees to other nearby elements. I
intend to twist the dipole 90 degrees real soon now. Hopefully this will
fix the problem. I have heard several complaints of similar interaction
problems on the SteppIR reflector
(http://groups.yahoo.com/group/SteppIR). I can't say whether the SteppIR
is more or less susceptible to such interactions than other antennas. I
can say that when it bothers another antenna in use, it's great to just
move it to a different frequency and see that interaction go away!
A friend here in CA has a 2el SteppIR fixed on the US East Coast at
modest height and loves it, especially the very short (<2m!) boom. I may
have been running my SteppIR too high (about 24m and located on a
ridge). In fact, at one time during CQP I lowered it to about 17 or 18m
and maybe, just maybe, it worked better on the higher bands at that
height. Too subjective to be meaningful.
I look forward to getting this antenna working to its potential and
maybe putting a second one lower on the tower. This isn't easy on a
crankup, especially with a 3el. The light weight of the antenna makes it
feasible, though, so I'm tempted. Also, they are working on a 4el design.
Hope this helps.
73,
/Rick N6XI
George Shaw wrote:
>Anyone using the SteppIR in a 2 or three element configuration? Good or
>bad? Value for the bucks (pounds/euro)? How high off ground? Minimum
>height requirements, turning circle etc.
>
>
>
>George Shaw MI3GTO
>
>Mobile: +44 (0) 7740 361 163
>Email: george.shaw@ukf.net
>
>
>
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--
Richard M. Tavan
TIBCO Software Inc.
3307 Hillview Drive
Palo Alto, CA 94304-1213
650-846-5214
tavan@tibco.com
20297 Hickory Hill Way
Saratoga, CA 95070
408-867-5797
n6xi@arrl.net
rtavan@alum.mit.edu
408-896-0476 Cell
530-587-3164 Getaway
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