Explain block diagram of distortion factor meter and explain how it operates
Fig. Distortion factor meter
Working : Initially the switch S is kept at position 1. The attenuator gets excluded and the bridge T network is adjusted for full suppression of fundamental frequency and hence we get minimum output condition. This condition indicated that the bridge T network is tuned to the fundamental frequency with full suppression of it. Then switch is moved at position 2, then the bridge T network is excluded. The attenuator is adjusted such that same reading as previous is obtained on the meter. Thus the total rms distortion is indicated by the reading of attenuator.