Overview - Keysight X Series Measurement Manual

Disturbance Analyzer (Click) Measurements

Overview

Overview
A broad range of commercially-available electronic devices exhibit intermittent
operation that generates impulsive (or discontinuous) radiated and conducted
disturbances. Common examples of these devices are washing machines,
refrigerators, thermostats, motor-operated apparati, and automatic dispensing
machines. The level of effective interference created by the discontinuous nature of
these disturbances is significantly different (and typically less) than the effective
interference created by a continuous disturbance.
To address this situation, CISPR (Comite International Special des Perturbations
Radioelectriques) developed different sets of conducted emissions limits for these
classes of devices. There is one set of limits for continuous disturbances and a
different set of limits for discontinuous disturbances, commonly called "clicks". The
definitions of a click, the measurement conditions and methodologies, and the limits
associated with different classes of equipment are all presented in the CISPR 14-1
International Standard document.
Because the effective level of interference caused by a discontinuous disturbance can
be less than the effective level of interference caused by a continuous disturbance,
CISPR limits for click amplitudes are relaxed from limits for continuous
disturbances. The amount of relaxation depends upon the rate of the measured clicks
over time. The lower the click rate, the greater the relaxation.
The following sections describe the operation of the Disturbance Analyzer
measurement application included in the Agilent N9038A MXE EMI receiver. It is
important to note that compliant discontinuous disturbance measurements require an
EMI receiver or a spectrum analyzer that is CISPR-compliant.
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