The Keysight (Agilent) 85644A Tracking Generator is a stimulus source accessory that synchronizes with compatible spectrum analyzers to perform high-dynamic-range frequency response measurements. The instrument sweeps in unison with the host analyzer, enabling scalar network analysis of amplifiers, filters, and RF/microwave components while minimizing spurious signal interference. The 85644A supports offset tracking for characterizing frequency translation devices and systems with propagation delays, power sweep capability for saturation analysis, and standalone CW signal generation without host instrument connection.
Technical Specifications
• Frequency range: 300 kHz to 6.5 GHz
• RF output power: Selectable, -80 dBm minimum leveled output
• Leveled output range: +10 dBm to -80 dBm
• Amplitude resolution: 0.01 dB
• Vernier range: >0.16 dB (Bands 0–3), >10 dB (Band 4)
• Dynamic range: Up to 140 dB (defined as difference between maximum tracking source power output and spectrum analyzer displayed average noise level, accounting for system losses)
• Offset tracking: >1 GHz capability for frequency translation and delay-line devices
• AC coupled output
• Accuracy: Referenced to 0 ±2 dBm at 300 MHz (low band) and 3 GHz (high bands), room temperature 20–30°C
– Key Features
• Synchronized swept stimulus signal for scalar network analysis
• Power sweep functionality for device saturation characterization
• Stand-alone CW signal generation mode
• Front-panel and HP-IB configuration access
• Portable package design: 26 × 22 × 12 in, 24 lbs
– Typical Applications
• Amplitude response characterization of active and passive RF/microwave components
• Mixer and frequency translator testing via offset tracking
• Saturation and compression analysis through power sweep
• Harmonic measurement using stand-alone CW mode
– Compatibility & Integration
The 85644A integrates with Keysight (Agilent/HP) 8560 Series, 8566A/B, and 8590 Series spectrum analyzers, as well as 8340A/B synthesized sweepers and 8350 Series sweep oscillators.
