The HP/Agilent 3585B is a high-performance spectrum analyzer covering 20 Hz to 40 MHz, engineered for precise baseband signal analysis in voice, video, and digital applications. This instrument delivers 80–100 dB spurious-free dynamic range with amplitude accuracy of ±0.25 dB across a measurement span of −137 dBm to +30 dBm. The 3 Hz minimum resolution bandwidth, combined with selectable 50 Ω, 75 Ω, and 1 MΩ input impedance, enables detailed characterization of low-level signals in complex environments.
## Technical Specifications
• Frequency range: 20 Hz to 40 MHz
• Resolution bandwidth: 3 Hz minimum; selectable 3 Hz to 30 kHz (1, 3, 10 sequence)
• Dynamic range: 80–100 dB spurious-free
• Amplitude accuracy: ±0.25 dB typical
• Measurement range: −137 dBm to +30 dBm
• Input impedance: 50 Ω, 75 Ω, 1 MΩ (selectable)
• Spurious responses: <−80 dB typical (relative to single signal at or below input range setting)
• Noise floor: −85 dBc average (1 kHz bandwidth); −115 dBm typical (3 Hz RBW, −8 dBm signal, 0 dBm input range)
• Built-in tracking generator: 50 Ω, 0 to 40 MHz, output −11 dBm to 0 dBm
• Frequency counter: 0.1 Hz resolution, 0.3 second measurement time
• Display: CRT with panel settings and marker readout
• Trace storage: 10 complete measurements in non-volatile registers; two simultaneous traces (1024 × 1001 points)
• Power requirements: 115 V (±11%, −25%), 48–440 Hz or 230 V (±11%, −18%), 48–66 Hz
• Power consumption: 180 W, 3 A max
• Probe power: +15 V dc, −12.6 V dc, 150 mA max
## Key Features
• Autoranging input attenuator optimizes dynamic range and minimizes distortion
• Fully synthesized tuning for CW and swept measurements
• Automatic peak search and signal tracking accelerate identification
• Automatic limit test evaluates all 1000 measurement points against user limits
• Noise level marker displays RMS noise density normalized to 1 Hz bandwidth
• Absolute and relative (signal-to-noise) marker functions
• Sweep gating option (Option 001) for burst signal analysis
## Compatibility & Integration
• HP-IB interface (IEEE 488-1978) with direct-plot capability
• External display outputs: X, Y at 1 V full deflection; Z from 2.4 V
• Compatible with HP active probe family
• Probe power: +15 V dc / −12.6 V dc supply available
