Question

Which of the following is not an example of sinusoidal oscillator?

(a) RC phase shift oscillator

(b) Weinbridge oscillator

(c) Crystal oscillator

(d) Blocking oscillator

I had been asked this question in class test.

I'd like to ask this question from Classification of Oscillator-1 in section Oscillators of Analog Circuits

Answer 1

The correct choice is (d) Blocking oscillator

Easy explanation: A blocking oscillator is a non-sinusoidal oscillator. It produces a free running signal-square shaped and requires only a resistor, transformer and one amplifying element to work. The transistor is blocked off for most of the duty cycle, producing periodic pulses.