FIELD: test of grinding materials produced from synthetic corundum and silicon carbide in process of manufacture of abrasive articles. SUBSTANCE: oscillatory circuit is formed by capacitor and inductance coil. Inductance coil is put on nonmagnetic form with magnetoconductive screen- concentrator. Internal hole of inductance coil is fitted with diamagnetic capsule to inject loose material subject to analysis. Buffer stage-current amplifier is connected to oscillatory circuit with its high-resistance input, output of buffer stage is connected in parallel to both two-stage amplitude voltage amplifier and to input of detecting- filtering unit. Two-way amplitude amplifier-voltage limiter and linear pulse amplifier connected in series are linked to output of two-stage amplitude amplifier-voltage limiter. Output of linear pulse amplifier is coupled through ballast-limiting resistor to high-resistance input of buffer stage-current amplifier and to said oscillatory circuit connected to it in parallel. Output of detecting-filtering unit is coupled through network comprising variable resistor and output of pointer-type indicator to mobile contact of potentiometric voltage divider connected to output of stabilized power supply source of collector networks. EFFECT: simplified design, enhanced functional reliability, easy handling and raised productivity of meter. 1 dwg
