MAS-3
2-30 MHz Multifunctional

Applications:
The MAS-3 multiport antenna system is designed for installations where space is at a premium and the communication requirements is for several circuits simultaneously having a variety of path lengths. It provides five independent antenna modes. Two of these modes are NVIS modes for short range skywave circuits; two are low angle modes for medium range circuits; and the fifth mode is a high gain rotatable log periodic antenna for long range circuits. The relatively small installation area together with the five independent antenna ports makes the MAS-3 ideally suited for congested antenna fields or sites where space is severely limited.
Features:
The MAS-3 multiport antenna system combines the four omnidirectional port capability of the SPQ-330 with the rotatable log periodic array (RLPA) features of the LPH-1A to provide a truly five port antenna system occupying the space normally required for a single antenna. All five ports may be used independently for transmit or receive. The RLPA has high gain, azimuth selection and permits communication between a fixed site and mobile stations such as ships and aircraft. It also features a torque tube and base-located rotator thereby providing high reliability and easy accessibility for inspections and maintenance. The spiral is a four-arm equiangular design wound on a pyramidal structure formed by the center support tower and four catenaries. It is fed using an AP four-port hybrid as protected under US Patent 5189434.
Optional Equipment:
Obstruction lights, erection kit, repair kit with winch, safety climbing equipment. Coaxial cable, connector adapters and mating adapters. Computer controller with RS-232 interface. A 230V 50Hz unit is also available.

Photos | Printable PDF File

SPECS. PORT 1 PORT 2 PORT 3 PORT 4 PORT 5
Application Short Range Medium Range Medium Range Short Range Long Range
Mode NVIS Low Angle Low Angle NVIS RLPA
Polarization Elliptical Vertical Horizontal Elliptical Horizontal
Frequency Range, MHz 2-30 MHz 4-30 MHz 4-30 MHz 2-30 MHz 2-30 MHz
Impedance, Ohms 50 50 50 50 50
VSWR 2:1 3.5:1 Max
2.5:1 Typical		 2:1 2:1 2.5:1
Directive Gain 7 dB 7 dB 7 dB 7 dB 9-12 dB
Power, kW 1 1 1 1 1
Input Connector Type "N" Type "N" Type "N" Type "N" Type "N"
Azimuth Pattern Omni Omni Omni Omni Directional
Primary Power N/A N/A N/A N/A 115 VAC
Rotation Speed N/A N/A N/A N/A 0.3 RPM
Typical Isolation 25 dB 25 dB 25 dB 25 dB 25 dB
Dimensions Height 106 Feet; Length 100 Feet; Width 100 Feet
Wind 100 MPH, no ice