The Keysight U1818B is an active differential probe engineered for high-frequency in-circuit measurements across network, spectrum, and signal source analyzers. Operating from 100 kHz to 12 GHz with ±1.5 dB flat frequency response, it delivers exceptional measurement fidelity on low-amplitude signals. A noise floor below -130 dBm/Hz (10 MHz to 12 GHz) enables detection of weak RF and digital signals. The probe accepts biasing directly from compatible Keysight instrument ports or standalone benchtop supplies, providing operational flexibility in laboratory and production environments.
Technical Specifications
• Frequency Range: 100 kHz to 12 GHz
• Frequency Response Flatness: ±1.5 dB
• Noise Floor: < -130 dBm/Hz (10 MHz to 12 GHz)
• Differential Input Impedance: 50 kΩ
• Nominal Probe Attenuation: -10 dB
• Common Mode Rejection Ratio: 35 dB (< 2 GHz); < 30 dB (2 GHz to 12 GHz)
• Operating Temperature: 0 to +55 °C
• Storage Temperature: -40 °C to 70 °C
• Operating Humidity: 50 to 90% RH at 40 °C (24-hour cycling, 5 repetitions)
• Storage Humidity: 90% RH at 65 °C (single 24-hour cycle)
– Key Features
• Wide bandwidth with consistent amplitude response across the measurement spectrum
• Low-noise front-end suitable for high-sensitivity RF and microwave characterization
• Flexible power delivery: integrated instrument ports or external supply compatibility
• High differential input impedance minimizes loading effects on test circuits
– Typical Applications
• RF and microwave component validation in R&D environments
• High-speed digital signal integrity analysis
• In-circuit measurements on wireline and wireless communication designs
• Aerospace and defense system verification and defect analysis
– Compatibility & Integration
Direct compatibility with Keysight network, spectrum, and signal source analyzers. Works with InfiniiMax II 12 GHz differential probe heads (N5380B SMA adapter, N5381B solder-in, N2839A browser, N5425B/N5426A ZIF types—ordered separately). Compatible with extreme temperature extension cables, in-line attenuators, minimum loss pads, DC blocking capacitors, and probe positioners.
