NRT Z-43 Directional Power Sensor The Rohde & Schwarz NRT-Z43 is a directional power sensor designed for precise RF power measurements. It operates from 400 MHz to 4 GHz, measuring average power from 0.0007 W to 30 W and peak power up to 75 W, with excellent directivity and low insertion loss. It can function independently or with a base unit, making it versatile for lab and field applications.