HP / Agilent 11678A Low-Pass Filter Kit

The HP/Agilent 11678A Low-Pass Filter Kit is a five-filter set designed to attenuate high-frequency components and harmonics in RF signal chains. Each filter provides selective frequency passing with sharp rolloff characteristics, enabling accurate measurements by eliminating out-of-band interference and noise. The kit covers frequency bands from 2.8 GHz to 13.0 GHz, matching HP 8620 Series Sweep Oscillator bands.

– Technical Specifications

The kit contains five individual filters with the following cutoff frequencies:

• 11688A: 2.8 GHz cutoff
• 11689A: 4.4 GHz cutoff
• 11684A: 6.8 GHz cutoff
• 11685A: 9.5 GHz cutoff
• 11686A: 13.0 GHz cutoff

Each filter exhibits insertion loss less than 1.1 dB at 0.95 fc and provides rejection greater than 40 dB at 1.25 fc. All filters present 50 ohm nominal impedance with Type-N female and male connectors. Net weight is 0.44 kg; shipping weight is 1.2 kg.

– Key Features

• Five complementary filters covering continuous RF measurement bands
• Low insertion loss maintains signal amplitude integrity
• High rejection characteristics suppress unwanted harmonics and out-of-band signals
• 50 ohm impedance matching for standard RF systems
• Type-N connectors for flexible integration

– Typical Applications

The 11678A kit is essential for broadband detector measurements where harmonic reduction directly impacts measurement accuracy. Use these filters in RF testing setups requiring harmonic suppression, signal conditioning before sensitive measurements, and noise reduction in frequency-dependent test configurations.

– Compatibility & Integration

The five filter set aligns with HP 8620 Series Sweep Oscillator frequency bands, enabling direct integration into legacy and modern RF measurement systems employing this instrument family.