The Keysight / Agilent / HP 11970A waveguide mixer is a general-purpose harmonic mixer employing a dual-diode design to achieve flat frequency response and low conversion loss. These are achieved without external dc bias or tuning stubs. Manual operation and computer-controlled hardware operation are simplified because mixer bias and tuning adjustment are not required.

11970A extends the frequency range of the Agilent E4440A/46A/48A PSA Series high-performance spectrum analyzers, the Agilent E4407B ESA-E Series portable spectrum analyzer, the Agilent 8560 E/EC-Series portable spectrum analyzers, the Agilent 8566B spectrum analyzer (used with the Agilent 11975A amplifier), and the Agilent 70000 modular measurement system (used with the Agilent 70907A/B external mixer interface modules)