The Agilent/Keysight K281C is a coaxial waveguide adapter that transitions between WR-42 waveguide and 3.5 mm coaxial systems across the K-Band frequency range. This bidirectional component enables power transmission in either direction, making it suitable for precision RF measurement and testing setups where impedance transformation between waveguide and 50 Ω coaxial architectures is required.
Technical Specifications
• Frequency Range: 18 to 26.5 GHz (K-Band)
• Impedance Transformation: Step-like internal structure converts waveguide impedance to 50 Ω coaxial line impedance
• Maximum SWR: 1.07
• Bidirectional Operation: Power transmission in either direction supported
– Key Features
• Excellent repeatability across measurement cycles
• Low standing wave ratio ensures minimal signal degradation
• Step-impedance design optimizes coupling efficiency
• Compact form factor; shipping weight 0.5 kg
– Typical Applications
• K-Band microwave testing and measurement environments
• Waveguide-to-coaxial system coupling in laboratory setups
• High-frequency characterization requiring precision transitions
• Bidirectional power measurement and calibration applications
– Compatibility & Integration
The K281C interfaces with WR-42 waveguides (EIA designation, MIL-W-85/1: 1-103) via UG-597/U flange (MIL-F-3922/54C: 002). Standard configuration features a 3.5 mm female coaxial connector; Option 012 provides 3.5 mm male connector for alternate configurations. The adapter integrates into test systems combining waveguide and coaxial measurement paths, accommodating flexible measurement architectures.
