Frequency selective wave analyser

Wave analyser

type• It of two type

• Resonant• Frequency selective wave analyser

USE• It is voltmeter which can accurately

tuned to measure amplitude of single frequency component

Use:

This wave analyser is used for measurement in audio frequency range (from 20Hz to 20KHz).

This wave analyser has a filter section with a very narrow pass band which can be tuned to the frequency of interest.

Precision Potentiometer are used to tune the filter to any desired frequency within the selection pass band.

Close tolerance polystyrene capacitors are generally used for selecting the frequency range.

Driver amplifier feeds the attenuated waveform to a high Q active filter.The filter consist of cascaded arrangement of RC resonant section and

filter amplifier

Input apply to attenuator is set by the meter range switch on front panel.This act as range mutliplier and permits large range of signal amplitude to

be analysed without loading the amplifier

Final amplifier stage supplies selected signal to the meter circuit and to an untuned buffer amplifier.

Buffer amplifier can be used to drive a recorder or an electronic counter.

Meter is driven by an average type detector and usually has several

voltage ranges as well as a decibel scale.

Bandwidth of instrument is very narrow, about 1% of selected

frequency.

Attenuation curve of wave analyser.

Thank You Engineers

DONE BY:

NIDHI MARU AKASH THAKAR