The Agilent 778D is a dual directional coupler engineered for bidirectional RF and microwave signal sampling across 100 MHz to 2 GHz. It delivers low insertion loss (36 dB to 1 GHz, 32 dB to 2 GHz), enabling accurate reflection and transmission measurements with minimal signal degradation. The multi-octave frequency span reduces setup complexity by consolidating multiple couplers into a single instrument.
Technical Specifications
Frequency Range: 100 MHz to 2 GHz. Coupling factor increases approximately 6 dB per octave below 100 MHz with directivity maintained above 36 dB; operation below 100 MHz depends on source power and RF detector sensitivity.
Coupling: Nominal 20 dB ±1.0 dB, with mean accuracy of ±0.5 dB.
Directivity: >36 dB to 1 GHz; 32 dB to 2 GHz.
Insertion Loss: <0.60 dB maximum on primary line.
Return Loss (SWR): Maximum 1.1 across primary line and auxiliary arms.
Power Handling: 50 W average; 500 W peak (10 µs duration).
Connectors: Type N female, Type N male, or APC-7 options. Type N connectors are stainless steel, MIL-C-39012 and MIL-C-71 compatible.
Physical: 425 × 111 × 30 mm (16.75 × 4.375 × 1.189 inches).
– Key Features
• Closely tracked auxiliary arms for reflectometer applications with sweep oscillators
• High directivity enabling precise forward and reverse signal isolation
• Bidirectional measurement capability in single instrument
• Broad frequency coverage minimizes multiport coupler inventory
– Typical Applications
• Reflection and transmission coefficient measurement
• Reflectometer configurations
• Network analyzer integration
• Impedance characterization
• Signal monitoring in RF/microwave test setups
– Compatibility & Integration
Works with Agilent 8508A and 8405A vector voltmeters for impedance measurements. Integrates with Agilent 8755 frequency response test set.
