I received my Skyhawk a couple of weeks ago and now have it up. The summary
is that it is an excellent antenna both electrically and mechanically. The
specifications are conservative. My non exact "on the air" measurements show
better results than the specifications. Bob Locher and Michael at Bencher
have demonstrated the highest degree of customer sensitivity and support
that I have seen in any industry. Bencher is really trying hard to have a
successful product.
Mechanically it is the best I have seen. Goes together quickly and easily -
all the elements are riveted. There are no measurements on any element or
the boom. All the location holes are preset. The elements are pinned to the
boom so they cannot rotate around the boom. Most impressive is that I did
not find one single aluminum chip, burr or sharp edge on any piece of the
antenna. Bencher has really taken care to produce a quality product.
SWR bandwidth is better than the specification. It is less than 1.4:1 across
the whole 20 meter band, less than 1.5:1 across the whole 15 meter band and
the worst SWR between 28 and 29 MHz was 2:1. Just outstanding and with no
traps the efficiency is very high.
I measured "on the air" front to back at least 30 dB and front to side
almost 40 dB. Please remember that this is measured off the air with QSB and
looking at an S meter but I am convinced that they have done better than the
specifications. When I turned the antenna 90 degrees to an interfering
station on 20 meters that was 10 over S nine he completely disappeared.
Whatever number of dB that is does not matter - this is the result I was
hoping for.
The antenna is mounted at 56 feet on an Aluma Tower here in Florida where
front to side reduction is important when looking at Europe. The feed line
is 175 feet of "Bury Flex" from Davis RF and includes Phasor lightning
protection. My thanks to many of you on this reflector for providing the
information, hints and construction suggestions that I have incorporated in
the system design.
I know this is not rigorous in terms of science but I ran multiple tests
against an 80 meter Radio Works Windom antenna at 30 feet to see how much
improvement I obtained with this installation. Typical reports from the
South Pacific, Europe, Middle East and the far Western USA were 20 over nine
on the beam and S7 on the Windom. The only meaning to this is that I can now
get DX on the first call and I am thrilled!
It also works well on 17 meters. The SWR is 2.5:1 but the tuner and the
Bencher balun handle this nicely. The pattern is reversed from normal
(shoots off the back instead of the front on 17 meters) and the gain and
directivity while not as good as on the main bands is still impressive.
There will be much debate on this but I am convinced that the computer
simulation work done by Dr. Jim Breakall in designing the antenna has been
successfully put into practice with the delivered product and with no traps,
a broadband SWR curve, light weight and low wind cross section (also
balanced for turning torque) this antenna is a winner. I believe the best
Tribander on the market today.
If anyone wishes more information please use direct e-mail:
tjednacz@ieee.org
Tom, W7QF in Dunnellon, FL
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