phase shift oscillator

**samieee** · Nov26-09, 01:06 PM

hi
i want to know why R-C oscillator is called phase shift oscillator? does it only shift the phase?How the amplitude and the frequency of oscillator ca be changed?
thanks

**berkeman** · Nov26-09, 09:48 PM

Originally Posted by samieee

hi
i want to know why R-C oscillator is called phase shift oscillator? does it only shift the phase?How the amplitude and the frequency of oscillator ca be changed?
thanks

Welcome to the PF. Could you please give more details about what you mean by an RC Oscillator? An RC all by itself won't make an oscillation, right? What else goes into an RC Oscillator? And what can you tell us about the definition of phase shift? What is it? Phase of what compared to what?

**samieee** · Nov27-09, 04:29 AM

Originally Posted by berkeman

Could you please give more details about what you mean by an RC Oscillator?

an oscillator having resistor and capacitor may be called an R-C oscillator.

**samieee** · Nov27-09, 04:44 AM

Originally Posted by berkeman

what can you tell us about the definition of phase shift? What is it? Phase of what compared to what?

phase shift means shifting the phase inversely by 180 degree.The phase of output signal compared to input signal.

**vk6kro** · Nov27-09, 08:04 AM

Do you mean this sinewave oscillator?

You can read about it here:

http://en.wikipedia.org/wiki/Phase_shift_oscillator

**sadcapehorn** · Dec1-09, 05:17 AM

I also want to know that.