The Agilent HP E4411A 1.5GHz Spectrum Analyzer has the performance of a high-quality spectrum analyzer and the rugged ease of use expected in a field instrument. The Agilent/HP  ESA-L1500A gives you a rapid display update rate and state-of-the-art 5 ms sweep time that reduces test time and increases throughput. The phase-locked synthesizer adds stability and repeatability to frequency measurements, and the automatic background alignment offers continuous calibration. Plus, you'll have specified performance only 5 minutes after power-up. 

Features :

• 4 ms RF sweep time
• Combined with 28 measurements per second, provides virtual real-time updates.
• Responsive display makes circuit adjustment easier, while increasing the probability of intercepting intermittent signals.
• High-speed data transfer (GPIB)
• Fast processing helps reduce measurement time in ATE environments.  
• Fully synthesized design
• Provides continuously phase-locked precision throughout the entire sweep.
• Improves frequency accuracy, stability, and measurement repeatability, eliminating drift.
• Amplitude correction
• Calibrates out frequency-related amplitude effects with built-in amplitude correction.
• Automatic background alignment Continuously calibrates the analyzer.
• Guarantees repeatability over changing temperatures. 85 dB calibrated display range
• Allows simultaneous display of large and small signals.