The Agilent/Keysight 3580A is a low-frequency spectrum analyzer engineered for detailed analysis of audio-range signals from 5 Hz to 50 kHz. It measures frequency components and amplitude characteristics across the low-frequency spectrum with 1 Hz resolution bandwidth capability. The instrument excels in signal analysis and two-port network characterization, providing 80 dB dynamic range and selectable sensitivity from +30 dBm to -70 dBm full scale.
Technical Specifications
Frequency Range:
• 5 Hz to 50 kHz
• Log sweep: 20 Hz to 43 kHz ±20% after 3 sweeps
Resolution Bandwidth:
• Six selectable options: 1 Hz, 30 Hz, 100 Hz, 300 Hz, 1 kHz, 3 kHz
• 1 Hz resolution available across entire frequency range
Amplitude Range:
• Linear: 20 V to 100 nV full scale
• Logarithmic: +30 dBm to -150 dBm (dB V equivalent)
• Eleven full-scale ranges via INPUT SENSITIVITY switch: +30 dBm down to -70 dBm
Dynamic Range:
• 80 dB
Frequency Response:
• ±3% across 5 Hz to 50 kHz (standard)
• Option 002: ±0.5 dB, 100 Hz to 20 kHz with 10 kHz reference and 600 Ω load
Sweep Characteristics:
• Sweep width: 50 Hz to 50 kHz
• Sweep times: 0.1 sec to 2000 sec
• Adaptive sweep threshold increases scan speed for signals of interest
• Manual mode provides cursor function; automatic modes display start or center frequency
Input Specifications:
• Capacitively coupled for DC isolation (standard)
• Maximum DC voltage: 100 V DC
• Input overload protection: momentary (<5 sec) up to 100 Vrms all ranges; continuous up to 100 Vrms on +30 dB through -10 dB, up to 50 Vrms on -20 dB through -70 dB
• Option 002 provides balanced input
Output:
• Main output: 0 to 1 V RMS into 600 Ω
• X-axis recorder: 0 V to +5 V ±2.5%
• Y-axis recorder: 0 V to +5 V ±2.5%
• Tracking oscillator: 1.0 MHz to 1.5 MHz as analyzer sweeps 0 Hz to 50 kHz
Calibration:
• Internal 10 kHz crystal-derived pulse for error compensation
• 10 kHz adjustment potentiometer included
– Key Features
• Digital storage trace memory for slowly swept low-frequency signals
• Single or dual trace simultaneous display for direct comparison
• Six selectable resolution bandwidths enable noise and spectral detail analysis
• 80 dB dynamic range resolves weak signals adjacent to strong carriers
– Typical Applications
• Audio frequency signal analysis
• Network analysis and transfer function measurement
• Low-frequency noise characterization
• Vibration and mechanical frequency assessment
– Compatibility & Integration
Recorder outputs (X and Y axes) interface with external plotters and data acquisition systems. Tracking oscillator output couples to external measurement equipment. Standard capacitive input accommodates single-ended sources; Option 002 supports balanced 600 Ω loads.

















