osicllator basics and theory

[shahabaz]

HI,
guys as am new to electronics i would like to more about basic oscillators its uses then its video tutorials.I need to lean them through net.

 

[Embedded_Geek]

Lecture - 1 Simple Harmonic Oscillators - NPTEL Quantum Physics Videos, NPTEL Physics Video Lectures, Physics Video Courses, Physics Video Classes, MIT Physics Video Lectures, Free Physics Video Lectures, Physics Video Tutorials, Physics Videos Cours

 

[shahabaz]

Thank you ajishgopalr for this video i need more and more explanations

 

[Embedded_Geek]

visit the following sites

1) **broken link removed**

2) oscillators

3) RC Oscillator Circuit

4) **broken link removed**

 

[LvW]

Thank you ajishgopalr for this video i need more and more explanations

Shahabaz, it is not possible to explain here the oscillation principle in detail.
*Just some basic rules: The keyword for an oscillatory circuit is "positive feedback". That means, you have to connect an amplification unit (gain A) and a passive and frequency-dependent network in a closed loop. This loop must have the following properties: The product of A and the damping factor d of the passive network must be unity (A*d=1) at one frequency fo only (the target oscillation frequency). At the same time, the phase shift of this product at fo must be zero.
*This leads to the common rule for a working oscillator (Barkhausen criterion):
Loop gain LG=A*d=1 (that means: real part unity and imaginary part zero).
*To understand the principle, here the most simple example:
The WIEN type oscillator consists of a RC bandpass (damping factor d=1/3 at fo) and an amplifier (opamp with negative feedback) having a again of A=3 - both connected in a closed loop.
Note, the above is a somewhat simplified description of the principle. Perhaps it helps.