AGILENT 778D DUAL DIRECTIONAL COUPLER 100MHz to 2GHz

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.