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Description
•
The F-718 is the U.S. version
of the F-718 UHF Base
Station/Repeater Antenna.
•
This antenna has been
optimized for the U.S.
Amateur Band.
•
Eighteen 1/2 wavelength
elements are phased to develop
11.5 db gain.
•
Two water tight joint assem-
blies connect three antenna
sections into one ridged
assembly.
•
The resulting antenna has the
same strength as a one piece
structure.
•
Protection from moisture is
achieved by use of ring gaskets
in each joint.
Assembly
1. Remove antenna sections from
packaging and note how the
sections are tapered and fit
together with metal joints.
Straighten inner coaxial element,
laying the sections in a
straight line.
2. Slide Upper fiberglass section
into Center section. Tighten Joint
Coupler with tow wrenches as in
Figure 3.
NOTE
: Gasket holders are placed
at marked locations 10 cm from
the lower end of Center Section
and 8 cm from the lower end of
Upper Section, they may have
moved during shipment. Be sure
they are correct before assembly.
3. Slide Center Section into Lower
Section. Tighten Joint Coupler
with two wrenches. Verify proper
placement of gasket holder as
was done above.
4. Fasten Radials and secure lock
nuts. (Figure 4.)
5. Attach mast brackets to Antenna
Support Pipe. Pass coaxial cable
through bottom of support pipe.
Connect coaxial cable to connec-
tor at bottom of F-718A. (Figure
5.) Align threaded hole at the bot-
tom of antenna with hole at top of
Antenna Support Pipe. Fasten
Antenna Support Pipe with screw
and washer. (See Figure 5.)
6. Attach F-718A to antenna mast
using brackets and hardware.
(Figure 6.) We suggest mounting
a one turn choke coil beneath the
antenna. Coil diameter is not
critical. NOTE: Some cables
require a larger diameter coil to
p r e v e n t
movement
of
center
conductor.
Tape coil to
mast. (See
Figure 6.)
F718A
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Base Station/Repeater Antenna
DIAMOND ANTENNA Products are distributed by RF PARTS COMPANY
435 S. Pacific S treet San Marcos, CA 920 78 (770) 614-7443
www.diamondantenna.net