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Radial wires can be laid on the roots of the grass using
DXE-STPL
Radial Wire Anchor Pins to
hold them down. Using enough staples will ensure the wires will not be snagged by mowers,
people, or animals. Grass will quickly overgrow the radials and they will be virtually impossible to
see or cause trouble. An article describing this process is available the DX Engineering website
www.dxengineering.com
in the
Tech Info
section. Radials can also be buried just under the surface
by using a power edger to make a slit in the soil.
Where the radial wires from one vertical element cross the radials of the other vertical element, they
should be cut and bonded (soldered) together using the optional
GCL-1120-050
Copper Radial
Cross Bonding Strap.
Vertical Antenna Information
Each full size quarter-wave vertical antenna should be resonant (reactance = 0) at the target
frequency for the particular band: 7.150 MHz on 40 meters for example. When the measurement is
being done on one vertical antenna, the other vertical antenna should be floating (not connected to
anything).
It is also expected that the impedance of a single full size quarter-wave vertical antenna should be
close to 39 ohms at resonance, as in 39 + j 0 ohms. That represents the 36 ohms of a "textbook"
quarter-wave vertical antenna, and a few ohms of ground loss, assuming a good ground.
When measured, one vertical with the other one floating, and the results are approximately 39 + j 0
ohms of impedance and then go to the second vertical with the first antenna now floating and again
measure 39 + j 0 ohms, that's a good indication of being ready to go.
Phasing Relay Unit Mounting Pipe
Use a customer supplied thick-walled galvanized steel mounting pipe
36
inches to 66 inches
long. This will allow approximately 12 to 18 inches
below ground and approximately 24 to 48 inches above ground. The height
above ground is to allow easy access to the connection on the Phasing Relay
Unit. A thick-walled steel pipe 1-3/4" OD to 2" OD
maximum
is
recommended with a minimum thickness of 1/8" (1/4" preferred) should be
used. The standard 1-1/2" galvanized water pipe (with a 1.9" OD) is just
fine for this application and can usually be found at your local home
building supply store. For permanent mounting, use a post-hole digger to
make the hole deep enough to accommodate the mounting pipe and a
couple inches of gravel at the bottom for drainage. Set the pipe on the
gravel, use the pre-mix concrete to fill around the pipe, adding water and
mixing as you fill or mix the concrete first, then pour in the hole. Fill the
hole until the concrete is level with the ground around it. Use a level as you
fill the hole to be sure the pipe is straight. Allow to set overnight. Your location, landscape and
