Wide-band digital tan-δ meter using a phase comparison system

The demand for precision in measurement of dielectric loss (tan δ), which is important to clarify the electrical characteristics of dielectrics of capacitors, etc., is increasingly becoming raised in level these days. The authors have published a direct-reading system of tan δ using the phase comparison method and developed a digital tan-δ meter based on the above. The next experiment was construction of a more compact sized all-electronic-type automatic digital tan-δ meter by using a MOSFET as the resistance element for the direct reading of tan δ. As the result of repeated investigations on the main circuits, an automatic digital tan-δ meter was successfully produced having a precision of 10^-3- 10^-4 at several 10 Hz-several 100 kHz.