hey frds,
i hv read details abt different types of oscillators like hartley ,phase shift and colpitts.i still am not able to understand the concept of oscillators properly that how it is possible to generate and ac signal output without an ac signal input.also wat r the advantages and disadvantages of each type of oscillator over the other. wat r oscillators used for in mordern electronics...
can anybody answer my questions or direct me to a proper source of information abt oscillators.
thank you very much

 

Please see rule #4: http://forum.allaboutcircuits.com/announcement.php?f=5

Oscillators use their own AC output, delayed a bit, as their AC input. We call this "feedback." The different types of oscillators delay the feedback in different ways. The ammount of delay determines frequency of oscillation.