Agilent/Keysight 70909A – RF Section Module

The Agilent/Keysight 70909A is an RF Section Module for the Keysight 70000 Series Modular Spectrum Analyzer. It delivers RF coverage from 100 Hz to 26.5 GHz using diode-pair mixing with low conversion loss and a built-in microwave preamplifier. The module supports external millimeter-wave measurements through switched LO routing to the front panel and compatibility with Keysight 11974 series preselected mixers.

Option Z40 extends preselected mixing to 40 GHz. Rear panel outputs include a 3 to 6.6 GHz local oscillator and intermediate frequencies at 321.4 MHz and 21.4 MHz, both at 50 Ohms impedance. Dynamic gain adjustment maintains consistent IF output relationships across the input attenuator range.

Technical Specifications

• Frequency Range: 100 Hz to 26.5 GHz


• Local Oscillator Output: 3 to 6.6 GHz (rear panel)


• Intermediate Frequencies: 321.4 MHz and 21.4 MHz (rear panel)


• First IF (High Band): 100 MHz to 700 MHz, tracking 21.4 MHz IF with -21 dBm ± 3 dB offset


• Output Impedance: 50 Ohms


• Dimensions: 24 × 12 × 12 inches


• Weight: 16.3 lbs

Key Features

• Diode-pair mixing architecture for reduced conversion loss


• Microwave path preamplifier enhances sensitivity


• Switched LO output accessible at front panel for external mixer applications


• Option Z40 integrates preselected mixing to 40 GHz


• SMB connectors for 21.4 MHz OUT, 300 MHz IN, and TUNE SPAN signals


• SMA connector provides first IF access in high band


• Multiple-pin connector supplies power and HP-MSIB control from mainframe

Typical Applications

• Signal analysis across microwave and millimeter-wave bands


• External mixer measurements using 11974 series preselected mixers


• Spectrum analysis requiring multi-stage IF architecture


• Frequency coverage extending to 40 GHz with Option Z40

Compatibility & Integration

• Keysight 70000 Series Modular Spectrum Analyzer mainframes


• Agilent 71209A spectrum analyzer


• 71910A wide bandwidth receiver


• Keysight 11974 series external mixers


• HP 70900A/B Local Oscillator Source