The Agilent/Keysight 8474B is a precision RF detector engineered for accurate power measurements across microwave and RF systems from 0.01 GHz to 18 GHz. Built around a gallium arsenide planar-doped barrier (PDB) detecting element, it delivers superior linearity and thermal stability compared to point-contact and Schottky diode alternatives.
Technical Specifications
Frequency Range: 0.01 GHz to 18 GHz
Frequency Response: ±0.35 dB across the full frequency range
Maximum SWR: 1.3
Low-Level Sensitivity: >0.4 mV/µW
Maximum Operating Input Power: 200 mW; typical short-term maximum 1 W (<1 minute)
Output Polarity: Negative (standard); positive available (Option 103)
Square Law Response: PDB detectors exhibit ≤3% response variation from 2 to 18 GHz. Option 102 (External Square Law Load) achieves ±0.5 dB deviation from ideal square-law response
Noise: <50 µV peak-to-peak (CW power at 100 mV output, 400 kHz bandwidth)
Operating Temperature: −65 °C to 100 °C
Connectors: Type-N male input; BNC female output
Dimensions: 59.86 mm × 41.15 mm × 37.36 mm
Weight: 85.3 grams
– Key Features
• PDB technology reduces square-law nonlinearity to 3% versus 9.5% for Schottky devices
• Exceptionally flat frequency response ensures accurate measurements across the 0.01–18 GHz band
• ESD hardening rated to 10 hits at 25 kV (body contact)
• Requires no DC bias; integrates directly with standard oscilloscopes
• Environmental qualification to MIL-STD 883 including vibration (20–200 Hz, 20g), shock (500g, 0.5 ms), salt atmosphere, and moisture resistance
– Typical Applications
• CW and pulsed RF power measurement
• Power leveling in swept microwave systems
• Frequency response characterization of microwave components
• Closed-loop power leveling circuits in microwave instruments
– Compatibility & Integration
The detector integrates a GaAs diode matched to 50 Ω transmission line with a miniature thin-film circuit. Type-N male input and BNC female output enable direct connection to standard RF measurement systems without external biasing.
