Which of the following statements are TRUE with reference to Q - meter?

1. Q - meter works on the principle of parallel resonance.

2. Q - meter useful in measuring the characteristics of coils and capacitors.

3. Q - meter consists of a variable calibrated capacitor and variable frequency AC voltage source.

4. Q - meter is used for the measurement of the quality factor, inductance, self-capacitance, bandwidth, and distributed capacitance of a coil.