8508 A Vector Voltmeter

The HP 8508A vector voltmeter is a fully automatic tuned receiver for RF voltage and phase measurements. The HP 8508A uses a narrowband measuring technique. The HP 8508A has dynamic range over 90 dB and sensitivity of 10 μV. The HP 8508A measures the phase difference between two input channels with at least 0.1 degree resolution over a full +180 degree to -180 degree range. The HP 8508A can be used for measurements such as electrical length, phase distortion, or impedance. The standard unit is supplied with the HP 85081B input module, which has two high-impedance probe inputs operating from 100 kHz to 1 GHz. Option 050 is supplied with the HP 85082A input module, whose 50 Ω inputs operate from 300 kHz to 2 GHz. The HP 8508A has an HPIB interface.^[3][2]

The HP 8508A is used for RF voltage and phase measurements. The HP 8508A can measure electrical length, phase distortion, and impedance. The HP 8508A can use any CW source as a stimulus, including a source that is part of the device being tested, so measurements can be made under normal operating conditions. The HP 8508A can store a reference and use it in later measurements, which allows individual circuit sections to be characterized and adjusted independently.^[3][2]