Model SD9-400 380-420 MHz 9 dBd. Gain 
 

TETRA BAND ANTENNA

Design Features: The SD9-400 ultra high performance TETRA band stacked dipole array is designed for use with highly populated radio sites requiring long haul omni-directional coverage. The SD9-400 is heavy duty stacked dipole array features, wide bandwidth, high gain, high power handling capacity, low VSWR, low noise performance and null filling coverage with omni-directional characteristics. This stacked dipole array maintains constant gain and VSWR over its entire 40 MHz bandwidth, making it highly suitable as base station antennas for TETRA systems, repeater, paging and any other multi-channel communication systems.
Constructions: The SD9-400 stacked dipole array uses 6063T6 ultra corrosion resistant architectural anodized aluminum, consists of Eight folded dipoles stacked vertically, fed in phase. The center fed dipole ends and cable connections to the dipoles are sealed in epoxy at the end of the boom for protection against weather and imparting rigidity and strength to the dipole structure. All fasteners are made of stainless steel.
Radiation Pattern: When the EIGHT dipoles are arranged 90 degrees apart around the central mast, 9dBd. omni directional radiation pattern results. Aligning the EIGHT dipoles collinearly (facing in one direction) a 12dBd. offset radiation pattern is obtained. The radiation pattern can be changed in the field by use of common hand tools. Vertical stacking distance is factory adjusted for highest efficiency.
Phasing Harness: Specially designed center fed phasing harness ensures equal and in phase signal distribution to all the eight dipoles. All power splitter joints are molded to avoid use of connector/adapters to minimize loss and molded N-Female antenna termination connector ensures complete waterproofing.
DC Ground: This Stacked Dipole Antenna operates at D.C. ground for protection against lightning. The dipoles are mounted on a tubular boom made of high strength aluminum alloy, which offers a low resistance discharge path against any lightning strike during stormy weather.
Shipping: The 6 Meters long central mast for mounting the dipoles is shipped in two sections of 3 Meters each for easy of shipping. The stacked dipole array is supplied with standard stainless steel pole mounting hardware. Side mounting hardware which includes the 1.35 Meters long two horizontal arms to hold the antenna on the side of the antenna tower can be supplied optionally to mount the antenna on side of a tower.

Electrical Specifications:
Frequency Range380-420 MHz
Gain9 dBd.
Bandwidth40 MHz
Antenna TypeDipoles
PolarizationVertical
Input Impedance50 Ohms
Radiation PatternOmni-directional
VSWR1:1.5
RF Power Handling Capacity500 Watts
Input TerminationN-Female
Lightning ProtectionDirect Ground

Mechanical Specifications:
Materials6063T6 Aluminum
Mounting Hardware -MaterialsMarine Grade Stainless Steel
Wind Rating200 Km/Hr.
Overall Length6 Meters
Shipping Length3 Meters
Maximum Mount Pipe Diameter 51mm (2 Inches)
Gross Weight18 Kgs.

Environmental Specifications:
Operating Temperature(-)30 to +70 Degrees Celsius
Storage Temperature(-)40 to +80 Degrees Celsius
Humidity0 to 95% RH