Hewlett Packard 8508A Vector Voltmeter + 85051B Input Module

The Hewlett Packard 8508A Vector Voltmeter paired with the 85051B Input Module is a precision dual-channel receiver for AC voltage magnitude and phase characterization of RF and microwave signals. This combination delivers high-accuracy measurements across an extended frequency range, enabling detailed impedance analysis, network characterization, and transmission/reflection measurements. The 85051B input module enhances measurement capability and extends the operational frequency envelope of the 8508A mainframe.

Technical Specifications

• Dynamic range: Over 90 dB


• Sensitivity: 10 µV


• Phase difference resolution: At least 0.1 degree


• Phase difference range: +180 to −180 degrees


• Search and lock time: 40 ms lockup within one range


• Maximum input: 2 V peak AC, ±50 Vdc


• A-channel minimum signal: 10 mV (100 kHz to 300 kHz); 1 mV (300 kHz to 3 MHz); 300 µV (3 MHz to 1 GHz)


• B-channel noise floor: 10 µV Input Configuration with 85051B Module


• Frequency range: Extends 8508A capability


• Input type: 50-ohm connectors


• Power requirements: 100/120/220/240 VAC, ±10%, 48 to 440 Hz, single phase


• Maximum power consumption: Typically 40 VA Physical Dimensions


• Standard configuration: 425.5 mm W × 133 mm H × 473.3 mm D


• Weight (net): 8.1 kg


• Option 001 with bail handle and protective cover: 524.5 mm W × 158.8 mm H × 524.5 mm D; net weight 9.4 kg

Key Features

• Dual-channel autoranging receiver for CW signal analysis


• Simultaneous measurement of two CW signal voltages plus phase difference between them


• Output display modes: voltage or power (linear or log), normalized magnitude and phase angle, real and imaginary components


• Built-in network analysis procedures for impedance and phase matching evaluation


• Calibration capability against known standards


• HP-IB interface for ATE integration and automated programming

Typical Applications

• RF and microwave component characterization


• Impedance and S-parameter measurements


• System calibration and validation


• Phase relationship analysis in dual-signal environments

Compatibility & Integration The 85051B input module is designed specifically to enhance the 8508A Vector Voltmeter. The combination supports HP-IB interfacing for seamless integration into automated test systems and remote operation configurations.