The Agilent/Keysight 3555B is a transmission and noise measuring set engineered for evaluating voice and data communication circuits. This instrument delivers the measurement capability needed for detailed analysis and troubleshooting of transmission systems, with particular strength in noise characterization across demanding dynamic ranges.
Technical Specifications
• Noise Measurement Range: -1 dBm to +121 dBm
• Level Measurement Range: -80 dBm to +31 dBm full-scale
• Frequency Response: Wide and flat across voice, program, and carrier frequencies
• Input Impedance (Terminated): 75, 135, 150, 600, or 900 ohms, balanced
• Bell System Conformance: Meets Bell System requirements
• Dimensions: 18 × 18 × 12 in.
• Weight: 12.0 lbs.
– Key Features
• Dual-range measurement architecture separates noise analysis (-1 to +121 dBm) from level measurement (-80 to +31 dBm), enabling precision across both weak and strong signal conditions.
• Multiple terminated impedance options (75, 135, 150, 600, 900 ohms, balanced) allow direct connection to legacy and modern transmission line configurations without adapters.
• Flat frequency response supports simultaneous evaluation across voice band, program frequencies, and carrier systems.
– Typical Applications
• Noise performance assessment in voice and data transmission circuits
• Transmission line characterization and troubleshooting
• Bell System-compliant measurement verification
• Multi-impedance circuit validation
– Compatibility & Integration
The 3555B is a mature instrument no longer in active production or direct support from Keysight. Operating and service documentation (part number 03555-90008) is available for reference. Integration with legacy test environments and transmission measurement racks remains viable for organizations maintaining installed systems.
