Abstract: A coin discrimination apparatus discriminates authenticity and a denomination of a coin by oscillation magnetic fields of high and low frequencies in a low frequency band in which generated magnetic fluxes allow a coin to pass therethrough. A first oscillation coil for generating an oscillation magnetic field of a low frequency and a reception coil are arranged at coin contact and coin non-contact surfaces, respectively, of an inclined coin path to face each other. A second oscillation coil is arranged on the coin non-contact surface to be separated from the reception coil by a predetermined distance in a coin rolling direction and generates an oscillation magnetic field of a high frequency.

Abstract: A called party response detecting apparatus includes a plurality of filter units for respectively detecting natural frequency components included in a plurality of signals sent from a telephone line. The apparatus also includes switching units for switching input levels of the filter units in a plurality of steps and a continuous signal detector for detecting that a logical sum output from the filter units has continued for a predetermined interval of time. An input level control unit operates to control the switching units to set an input level at a lowest level while waiting for a signal and also to reset the input level at a predetermined level different from the lowest level when an output is obtained from one of the filter units. During this reset operation, the input level control unit decreases the input level in steps until an output is obtained from the continuous signal detector.