12 - Measurands and measurement equipment

Abstract

This chapter discusses various measurands and the measurement equipment. Where more than one method may be used to measure the measurand, these are then listed alphabetically, too, according to the equipment. In many cases measurement of a measurand is undertaken simply by using a transducer, which converts the measurand into an electrical quantity, for instance, voltage, current and so on, which is measured using fairly basic equipment. Electronic test equipment is used to measure a number of aerial parameters, such as, directivity, gain, impedance, radiation resistance, resonant frequency, and transmitted power. There are two main types of untuned amplifier: audio and video. Audio amplifiers and circuits operate to amplify or adjust signals within the audio hearing range. Video amplifiers and circuits do similar with signals over a wider band of frequencies. Furthermore, increasing use of optical fibers in communications systems has prompted a surge in the usage of associated test equipment. Most of the measurands which need to be measured, however, remain similar and analogous to those of non-optical fiber communications.