F-718 Series Instruction Sheet
Note: The F-718 antenna package is used for the entire series of F-718 antennas. A label on the outside of the
package designates antenna frequency range.
• 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 assemblies 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.
Specifications
Frequency:
420-430 MHz
Model F-718L
430-440 MHz
Model F-718J
440-450 MHz
Model F-718A
460-472 MHz
Model F-718C2
Gain:
11.5 db
Impedance:
50 ohms nominal
VSWR:
1.5:1 (typical)
Power Rating:
250 watts
Element Phasing:
18 1/2 wavelengths
Radials:
Three
Grounding:
Antenna element & radials connected to mounting pipe
Max. Wind Rating:
90 m.p.h.
Mast Dia. Acceptance:
1.2 to 2.4 inches
Length:
15 ft.
Weight:
4 lbs.
Connector:
Type N female
Limited Warranty:
90 days against defects in material or workmanship
Assembly Instructions
(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 connector at bottom of F-718A. (Figure 5.) Align threaded hole at the bottom 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 prevent movement of
center conductor. Tape coil to mast. (See Figure 6.)
DIAMOND ANTENNA Products are distributed and warranted by RF PARTS COMPANY
435 S. Pacific Street • San Marcos, CA 92069 • (760) 744-0900
www.diamondantenna.net
