chapter  35
Oscillators and waveform generators
Pages 12

Negative feedback is achieved by subtracting a fraction of the output signal from the input signal of an amplifi er. In practice, this is done by adding back the feedback signal in antiphase, so that feedback from an output which is in antiphase to an input is always negative unless some change of phase occurs in the circuit used to connect the output to the input (see later, under Oscillators for low frequencies).