Q. What is a clamper? Differentiate between a clamper and clipper.

Clamping network shifts (clamps) a signal to a different dc level, i.e. it introduces a dc level to an ac signal. Hence the clamping network is also known as dc restorer. These circuits find application in television receivers to restore the dc reference signal to the video signal. During the positive half cycle, the diode conducts, i.e. it acts like a short circuit. The capacitor charges to V volts. During this interval, the output which is taken across the short circuit will be V_o = 0 V. During the negative half cycle, the diode is open.

The difference between clipping and clamping circuits is that while the clipper clips off an unwanted portion of the input waveform, the clamper simply clamps the maximum positive or negative peak to a desired dc level.