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 Model SD3-400 380-420 MHz 3 dBd. Gain 


Design Features: The SD3-400 ultra high performance TETRA band stacked dipole array is designed for use with highly populated radio sites requiring long haul omni-directional coverage. The SD3-400 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 SD3-400 stacked dipole array uses 6063T6 ultra corrosion resistant architectural anodized aluminum, consists of two 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 two dipoles are arranged 180 degrees apart around the central mast, 3dBd. omni directional radiation pattern results. Aligning both dipoles collinearly (facing in one direction) a 6dBd. 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 both the 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.
Direct 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 antenna can be supplied in assembled or dismantled condition as per customer choice. The stacked dipole array is supplied with standard stainless steel pole mounting hardware.

Electrical Specifications:
Frequency Range380-420 MHz
Gain3 dBd.
Bandwidth40 MHz.
Antenna TypeDipoles
Input Impedance50 Ohms
Radiation PatternOmni-directional
VSWR - Equal To or Better Then1:1.5
RF Power Handling Capacity500 Watts
Input TerminationN-Female
Lightning ProtectionDirect Ground

Mechanical Specifications:
Antenna Materials6063T6 Aluminum
Mounting Hardware -MaterialsMarine Grade Stainless Steel
Wind Rating200 Km/Hr.
Overall Length1.6 Meters
Shipping Length1.6 Meters
Support Pipe O.D.51 mm
Support Pipe MaterialAluminum Tube
Maximum Mount Pipe Diameter 51 mm ( 2 Inches)
Gross Weight5 kgs

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