The Agilent/Keysight X281C is a waveguide-to-coaxial adapter that transitions between EIA WR-90 waveguide transmission lines and 50-ohm coaxial systems. Operating across the X-band frequency range of 8.2 GHz to 12.4 GHz, this adapter supports bidirectional power transmission with exceptional return loss performance. The stepped internal impedance-matching structure delivers a maximum SWR of less than 1.3 across the full band, with achievable performance of 1.05 SWR. The standard configuration pairs a UG-135/U waveguide flange with an APC-7 coaxial connector, though Type-N (male) alternatives are available as Option 012. Precision-engineered for RF and microwave measurement systems, the X281C meets NIST-traceable calibration standards and is constructed for demanding laboratory and field applications.
Technical Specifications
• Frequency Range: 8.2 GHz to 12.4 GHz (X-Band)
• Waveguide Interface: EIA WR-90 with UG-135/U flange
• Coaxial Connector: APC-7 (50 Ω)
• Maximum SWR: Less than 1.3 (typical 1.05)
• Power Transmission: Bidirectional
• Internal Architecture: Step-matched impedance transformer
– Key Features
• Low return loss across full X-band coverage
• Impedance-matched 50-ohm termination
• Calibration traceable to NIST standards
• Optional Type-N (male) connector configuration (Option 012)
• Optional alignment holes for repeatable flange positioning (Option 006)
– Typical Applications
• X-band test and measurement systems
• Waveguide-to-coaxial conversion in network analysis
• Microwave signal routing and distribution
• Two-way transmission in RF test setups
– Compatibility & Integration
The X281C interfaces standard EIA WR-90 waveguide transmission lines with 50-ohm coaxial instrumentation. The APC-7 connector mates directly with laboratory-grade RF equipment. Alternative Type-N connectors accommodate legacy systems or field installations where coaxial continuity requires different termination.
