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 Model QHA-150 135-175MHz 3 dBic Gain 


Design Features : QHA-150 broadband omni-directional RHCP quadrifilar helix or LHCP quadrifilar helix antenna is rugged all weather model, enclosed in a fiber glass radome, uses high class copper alloy and does not require any field tuning or adjustments. The compact size of LHCP or RHCP omni-directional quadrifilar helix antenna allows easy handling, shipping and highly suitable for receiving, transmitting, scanning, monitoring, surveillance and jamming applications without having the requirement of multiple antennas. The antenna is also highly suitable for Ground to Air communication/jamming application due to its wide elevation beamwidth with omni-directional properties. Antenna termination fitted just below the NATO mounting flange for complete weather protection. Other type of mounting hardware / configuration can be supplied on request.

Constructions :The QHA-150 LHCP or RHCP quadrifilar helix antenna is consisting of two (pair) vertical loop radiating elements at right angles to each other, twisted into a helix turns vertically and enclosed in fiber glass radome. The special “Teflon Dielectric Transmission Line” technique is used to handle high power handling capacity allowing smooth VSWR and typical 3dBi. gain over the specified frequency band. The fibe glass enclosure has excellent transparency for RF signals and enough strength to withstand specified wind loads. The stainless steel mounting hardware is supplied with the antenna. Cylindrical shell/enclosure is used for low wind loading and for minimal effect of ice formation on the antenna operation as well as providing an aesthetically pleasing appearance.

Electrical Specifications:
Frequency Range135-175MHz
Gain3 dBic
Bandwidth20 MHz
PolarizationCircular - RHCP or LHCP
Input Impedance50 Ohms
Radiation PatternOmni-directional
Beamwidth -3dB.120 Degrees (Vertical)
VSWR - Equal To or Better Then2:1
RF Power Handling Capacity1000 Watts
Input TerminationN-Female

Mechanical Specifications:
Antenna MaterialsCopper, Fiberglass
Mounting Hardware -MaterialsMarine Grdae Stainless Steel
Wind Rating150 Km/Hr.
Mounting TypeVertical Pole/Mast Mount
Overall Length1300 mm
Shipping Length1400 mm
Maximum Mount Pipe Diameter 77 mm (3 Inches)
Radome MaterialFiber Glass
Radome Outer Diameter1150 mm
Radiating Elements - MaterialHigh Quality Copper
Gross Weight20 Kgs.

Environmental Specifications:
Operating Temperature(-) 30 to +60 Degrees Celsius
Storage Temperature(-) 40 to +70 Degrees Celsius
Humidity0 to 95% RH