The SYST-A0004 is a DF and Monitoring stack comprising DF-A0038 vertical polarisation DF and Omni, and OMNI-A0099 and OMNI A0100 horizontal omni antennas. At the base it is supported by the MISC A0047 support cage. All RF and control signals pass through the MISC A0045 amplifier block which compensates for cable losses.
Mounted on a mast, with vertical and horizontal polarisation monitoring, and interferometric direction finding, it provides a complete spectrum monitoring and DF solution. A DF switch can be mounted at the base of the DF array. Its cables can be fed back into the mast and routed through the omnis.
The horizontal-polarisation omni antennas feature a cable duct for connection of antennas above, G223 without distortion of their patterns. All monitoring antennas share a common axis, giving excellent radiation patterns.