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 Model SD-127 118 - 137 MHz. 3 dBd. Gain 


Design Features: The SD-127 Aviation Band Antenna is manufactured using high-grade anodized aluminum. Powder coating of the complete aviation band antenna provides extra protection against corrosion in saline weather present in coastal areas. The SD-127 stacked dipole array operates at DC ground from protection against lightening, does not require any field tuning or adjustment and is highly suitable for ground-to-air communication with ATC sites without having the requirement of multiple antennas. The SD-127 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.

Constructions:The SD-127 Stacked Dipole Array consists of TWO folded dipoles stacked vertically, fed in phase. This Stacked Dipole Antenna operates at D.C. ground for protection against lightning. Termination of phasing harness cable sealed by heat shrinking tube making stacked dipole antenna waterproofing. The 3 Meters long central mast for mounting the dipoles is shipped in two sections of 1.8 Meters each for easy of shipping. The stacked dipole antenna is suitable for mounting on the top of tower and is supplied with two mounting brackets.

Radiation Pattern: When the TWO dipoles are arranged 180 degrees apart around the central mast, 3dBd. (5.15dBi) omni directional radiation pattern results. Aligning the TWO dipoles collinearly (facing in one direction) a 6dBd. (8.15dBi) offset radiation pattern can be obtained. The radiation pattern can be changed in the field by use of common hand tools.

Electrical Specifications:
Frequency Range 118 - 137 MHz.
Gain3 dBd.
BandwidthEntire Band
Antenna TypeDipoles
Input Impedance50 Ohms.
Radiation PatternOmni Directional
Beamwidth -3dB.40 (Vertical)
VSWR - Equal To or Better Then2:1
RF Power Handling Capacity600 Watts.
Input TerminationN-Female
Lightning ProtectionDirect Ground

Mechanical Specifications:
Mounting Hardware -MaterialsStainless Steel
Weight Approx10 Kgs.
Wind Rating210 Km/Hr.
Overall Length3.6 Meters.
Support Pipe Aluminum - Outer Diameter. Aluminum 50 mm
Dipoles Aluminum - O.D.Aluminum 12.7 mm
Shipping Length1.8 Meters.
Maximum Mount Pipe Diameter 52 mm (2 Inches)
Radiating Elements
- Material
- Cross Section

Aluminum Tube
Round - 12.7 mm O.D.

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