Keysight (Agilent) 8903A

The Keysight (Agilent) 8903A is a microprocessor-controlled audio analyzer that combines audio source, distortion analyzer, frequency counter, AC voltmeter, DC voltmeter, and SINAD meter functionality in a single instrument. It delivers precise audio signal characterization across 20 Hz to 100 kHz with output distortion below 0.003% typical at 1 V.

The audio source provides selectable 50 Ω or 600 Ω output impedance for unbalanced connections. Output level accuracy reaches ±1% of setting from 20 Hz to 50 kHz and ±2% from 20 Hz to 100 kHz into 600 Ω load, with 0.35 V resolution or better. The analyzer section measures AC levels from 0.3 mV to 300.0 V full scale with accuracy specifications ranging from ±2% to ±4% of reading depending on frequency and level ranges. True RMS responding AC converter ensures accurate noise measurements, while 3 dB bandwidth exceeds 500 kHz.

Distortion measurement capability extends down to below 0.003%. SINAD measurement ranges from 0 to 99.99 dB with 0.01 dB resolution. Signal-to-noise ratio (SNR) measurement spans 0 to 99.99 dB. The integrated frequency counter operates from 20 Hz to 150 kHz with 8 ms per reading in rapid mode.

– Technical Specifications

• Frequency Range: 20 Hz to 100 kHz (analyzer and source); 20 Hz to 150 kHz (frequency counter)
• Output Distortion: Less than 0.003% (typical, at 1 V)
• Output Level Accuracy: ±1% of setting (20 Hz to 50 kHz); ±2% of setting (20 Hz to 100 kHz)
• AC Level Measurement Range: 0.3 mV to 300.0 V full scale
• Distortion Measurement: Down to <0.003%
• SINAD Measurement Range: 0 to 99.99 dB with 0.01 dB resolution
• SNR Measurement Range: 0 to 99.99 dB
• Frequency Counter Rate: 8 ms/reading (rapid mode)
• 3 dB Bandwidth: Greater than 500 kHz
• Output Impedance: 50 Ω or 600 Ω selectable
• Power Requirements: 100, 120, 220, 240 VAC, 50/60 Hz, 100 VA

– Key Features

• True RMS AC converter for precise noise characterization
• Floating input/output with up to 60 dB common mode rejection
• Low-pass filters at 30 kHz and 80 kHz; high-pass filter at 400 Hz
• Psophometric filter for CEPT standards compliance
• Automatic tuning and autoranging for simplified operation
• Single or two-keystroke measurement execution

– Typical Applications

• Transceiver audio measurements
• Audio stimulus/response characterization
• Automated test equipment (ATE) systems
• General audio equipment validation

– Compatibility & Integration

• HP-IB (IEEE-488) interface for remote operation and ATE integration
• Programmable control for complex test sequences