(1) A signal source capable of producing high quality sine wave of different frequencies is required to determine the frequency response of an amplifier.
(2) saw tooth waves of various frequencies are used as time basesignal for proper operation of CRO.
(3) A square wave or a waveform derived from it is used as timing signal to control different operations of a digital ckt.
The circuit which generates various type of waveform is called waveform generator or signal generator or oscillator.
Types of oscillator.
(1) Sinusoidal oscillator:- Oscillator capable g generating pare sine wave.
(2) Relaxation oscillator:- oscillator which generator other types of waves.
Oscillators may be classified as:-
(1) Feedback oscillator
(2) Negative resistance oscillator
(3) Relaxation oscillator(4) Miscellaneous type oscillator