The ALT-930-2M Triple Loop Antenna is designed based on the Loop Antenna System (LAS) described in Annex C of CISPR 16-1-4. The antenna consists of three mutually perpendicular large loop antennas having diameters of two (2) meters.

The loops are constructed from high quality RG 223/U coaxial cable, inside flexible 1” PEX pipe. The three (3) loops connect to three (3) current to voltage transducers, the outputs of which connect to three respective inputs on a coaxial switch.

The switch is used to select which loop connects to the measuring instrument, while terminating the other two loops into 50 ohms. The switch can be controlled locally or remotely via fiber optic interface with the optional RLI-100 Remote Interface.

The antenna assembly is supported by a fiber glass/plastic mounting structure employing swivel casters, enabling the antenna to easily be moved without disassembly.

Application

The primary application for this antenna is the measurement of radiated magnetic fields (or radiated electromagnetic disturbances) generated by various types of electrical lighting and similar equipment while located in the approximate center of the Triple Loop Antenna structure, as per the requirements of CISPR 15 (EN 55015).