The Keysight / Agilent / HP 435B power meter is an analog power meter, compatible with the entire series of 8480 power sensors. Depending on which sensor is used, the 435B can measure power from -65 dBm to +44 dBm, full scale, at frequencies from 100 kHz to 110 GHz. This versatile instrument also features <1 percent instrumentation uncertainty, low noise and drift, auto-zero, recorder output, optional battery operation, and long cable options up to 61 m (200 ft).