Draw block diagram of distortion factor meter and explain its operation.
Block Diagram
Operation
This meter consist following four sections
1. Impedance converter along with input circuit
2. Rejection amplifier
3. Metering circuit
4. Power circuit
1. The impedance converter provides a low noise , high impedance input circuit , independent of the signal source impedance placed at the input terminals to the instrument
2. The rejection amplifier rejects the fundamental frequency of the input signal and passes the remaining frequency to the meter.
3. The meter has visual indication of the THD in term of percentage of the total input voltage.
4. The power supply unit provides the supply for proper operation