Inside Phil's station is a Yaesu FT-1000MP transceiver with an INRAD
4 kHz roofing filter, an ETO/Alpha Power 91b 1500 watt linear
amplifier, a Ten-Tec 1208 20 meter to 6 meter transverter, a Mirage
A1015 150 watt 6 meter amplifier, and an Amteritron ATR-30 HF antenna
tuner. The station computer is homebrew and has an AMD Athlon
T-Bird 1.2 GHz CPU and 1 GB of RAM. Phil uses DXLab for daily
logging and DX Cluster use and WriteLog when operating in contests.
For 2 meter FM operation, a Yaesu FT-1802M 50 watt base radio and an
Yaesu VX-170 HT are available. For HF and 2M mobile operation, Phil
uses an Icom IC-706 MkII trasnceiver with a High Sierra HS-1500 HF
screwdriver vertical and a 1/4 wavelength 2 meter whip antenna.
A Cushcraft Ringo Ranger for the 2 meter band is side-mounted
at about 55 feet above ground for FM use. Not visible in the photo
is a garage roof tripod support with a four-element HyGain Yagi for
6 meters mounted 27 feet above ground. The 6 meter antenna is
turned by a HyGain TailTwister rotor and fed with 7/8" heliax for
low loss.
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Seven sections of Rohn 45G tower at NA4M support a Bencher Skyhawk
triband antenna for 20 meters, 15 meters, and 10 meters at 73 feet
above ground, and a Cushcraft 40-2CD two-element 40 meter antenna at
78 feet above ground. The Skyhawk and the 40-2CD are turned by a
refurbished WWII-vintage aircraft prop-pitch motor controlled by an
M2 rotor controller.
The Skyhawk replaces a stacked/phased pair of HyGain TH7s. Phil
wanted to use one of the newer generation of computer designed
antennas after many years of service from the TH7s. One of the
old HyGain antennas began service in 1971 as a TH6 and only later
converted to a TH7.
All currently available triband, quadband, and log-periodic directive
antennas were studied and evaluated over the last few years before
the decision was made to go with the Skyhawk. The Skyhawk has a total
of 10 monoband elements, and there are no traps or linear loading in
any element. The antenna has three elements on 20 meters, three
elements on 15 meters, and four elements on 10 meters. The three
separate driven elements are all fed in parallel simultaneously by
a common coax and balun. The boom is 24 feet long and has double-
and triple-wall construction; no boom support truss is needed. The
antenna also has torque and wind compensators to ease the strain on
the rotor.
Another key feature that sold Phil on this antenna was its mechanical
design, which includes its simple feed system and great element to
boom mounting hardware. The only pop rivets in the antenna are used
to connect the element tubing sections together. All other fastener
hardware is stainless steel bolts and screws. So far, Phil feels that
the electrical and mechanical performance of the Skyhawk has met or
exceeded his expectations in all respects.
Close to the top of the tower is a wooden side arm that supports an
80 meter full-wave delta-loop antenna that is fed one quarter
wavelength from the apex for low angle vertical polarization. The
tower also is shunt-fed for 160 meters over sixteen in-ground short
radials. Out in the south side yard is a pair of K9AY desgin
receive-only loops used for 80 meters and 160 meters. Phil switchs
between the loops with a K9AY Loop Control remote switch box
that has an in-shack control box.
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