The HP-Agilent-Keysight 70621A is a low-noise preamplifier module for RF and microwave spectrum analysis systems. Operating from 100 kHz to 2.9 GHz, it integrates into HP 70000 Series mainframes as a 1/8-width module to enhance system sensitivity and reduce noise figure in front-end measurement configurations. The preamplifier delivers high-gain amplification for detection of low-level signals and includes a front-panel +28 V dc output for noise-source drive voltage. Built-in bypass switches allow preamplifier engagement or disengagement without removing the module.
## Technical Specifications
• Frequency Range: 100 kHz to 2.9 GHz
• Noise Source Drive Voltage: +28 V dc output (front panel)
• Module Configuration: 1/8-width for HP 70000 Series mainframes
## Key Features
• Low-noise, high-gain amplification stage for sensitivity enhancement
• Reduces system noise figure for improved signal detection at threshold levels
• Enables noise figure measurements when paired with spectrum analyzer systems
• Integrated bypass capability via front-panel switches
• Modular plug-in design with no external connections required
## Typical Applications
• RF spectrum analysis requiring enhanced sensitivity
• Low-level signal detection in microwave measurement systems
• Noise figure characterization in receiver chains
• System noise performance optimization in 100 kHz to 2.9 GHz band
## Compatibility & Integration
The 70621A requires HP 70900 Local Oscillator firmware version 900314 or later. It operates within the HP 70000 Series modular architecture and coordinates with HP 70600A or HP 70601A preselectors to manage input overload conditions and multiple responses. An upgrade kit may be supplied with specific configurations to meet firmware requirements.
