HP / Agilent 35678B Type-N Calibration Kit

The HP/Agilent 35678B Type-N Calibration Kit is a precision calibration accessory for network analyzers and S-parameter test sets operating at 75 Ohm impedance. This discontinued kit delivers calibration standards essential for accurate RF and microwave measurements, enabling removal of systematic errors including directivity, port match, and frequency tracking effects.

## Technical Specifications

• **Connector Type:** Type-N
• **Impedance:** 75 Ohms
• **Manufacturer:** Hewlett-Packard / Agilent / Keysight
• **Model:** 35678B
• **Status:** Discontinued; legacy support available through Keysight

## Key Features

The kit comprises precision calibration standards in a carrying case. Typical components include shorting plugs/jacks, adapters, and precision terminations. Included standard part numbers vary by unit and may include 26N75, 26NF75, 1250-1530, 1250-1531, 1250-1528, and 1250-1529. Each standard maintains the specified 75 Ohm characteristic impedance.

Calibration accuracy directly depends on the precision and traceability of included standards. The kit supports both Short/Open/Load/Thru (SOLT) and Thru/Reflect/Line (TRL) calibration methodologies.

## Typical Applications

• Network analyzer error correction and system calibration
• S-parameter measurement validation
• Verification of test port performance
• Removal of systematic measurement errors from RF/microwave test setups

## Compatibility & Integration

The 35678B integrates with network analyzers featuring Type-N connector ports. It pairs effectively with S-parameter test sets such as the HP 35677A/B. Used units are available in good working condition, with cosmetic wear typical of legacy equipment. Keysight Service Centers continue to offer repair and calibration services for this discontinued product line.