Diamond Antenna A144-S5 User manual

A144-S5
2 Meter Yagi Antenna
Specifications
Frequency: 144-148 MHz
Gain: 9.1 dBi
Power Rating: 100 Watts
Impedance: 50 Ohms (Nominal)
VSWR: 1.4:1 (Nominal)
Front To Back Ratio: 17 dB
Boom Length: 37.4” 950mm
Longest Element: 42.9” 1090mm
Driven Element diameter: 0.50” 12.7mm
Parasitic Elements diameter: 0.37” 9.4mm
Max. Mount diameter: 1.5”
Weight: 0.4 lbs. 0.81 kg
Antenna Assembly
(1) Remove antenna from package and adjust elements to proper position. You will find a small mark on the center of each
element to aid in its positioning. Tighten each wingnut after verifying proper positioning.
(2) Weatherproofing connections. As coaxial cables tend to absorb moisture through their connectors, it is recommended
that the connector be sealed. There are several products available for this purpose, including a good grade of electrical type
or a rubber compound tape.
Figure 1
Figure 2
DIAMOND ANTENNA Products are distributed by RF PARTS COMPANY
435 S. Pacific Street •San Marcos, CA 92078 •[phone]
www.diamondantenna.net
←6” →
Fabricated
extension
↑

The Diamond 2 Meter Beam Antennas are easy to assemble and install. Only a few cautions are necessary in their installation.
The A144S5 may be installed for either vertical or horizontal polarization.
(a) Vertical polarization (preferred for FM operation): If mounting to a vertical support or pole at the boom center, be
sure this support is non-metallic. A fiberglass or waterproofed hardwood extension should work satisfactorily. End mounting is a
good option, as the coax cable may be run along the boom and down the vertical support. The idea is to minimize the effects of
metal in the vertical plain. It will be necessary to fabricate an extension capable of sliding inside the boom, being secured by the
screw passing through the boom (at the reflector element). Another way of mounting vertical beams is on a bracket to position
beam away from the vertical support in order to reduce its effects. Coax should be run away from the beam at right angles (or off
the reflector end). See Figure 2.
(b) Horizontal mounting to the vertical support is easily accomplished with center boom mounting.
(c) Phasing of two beams may be accomplished with a special coax phasing section using 75 ohm coaxial cable and T-
connector. Length approximately 2140 mm / 84 inches. Beam separation of approximately 40”-48” is recommended.
Note that the two antennas are mounted to the stacking boom in the same position. The cable connection must enter
each from the same side as shown in Figure 4.
Figure 3
Tighten Wingnuts
Position element for
center marker
Figure 4