INSPECTION METHOD FOR MAGNETIC HEAD

PURPOSE:To eliminate the need for a magnetic medium and to make the measurement accurate by allowing an oscillator to send an AC signal and giving the signal to a magnetic head via a transformer and applying a DC current to an erasure coil at the same time. CONSTITUTION:When an AC signal from an oscillator 15 is impressed to the primary side of the transformer 16, a signal induced in the secondary side is impressed to an intermediate tape of the coil of a read/write corer via a terminal 11d and a current flows to ground via resistors R1, R2 and a prescribed voltage is generated across the resistors. The amplitude of two signals generated across the resistors R1, R2 is entirely identical when a switch 18 is turned off. When the switch 18 is turned off, however, a prescribed DC current flows to the erase core 11b and a DC magnetic field is generated. The leakage magnetic field due to said DC magnetic field gives effect on the coil of the read/write core 11a and a difference is caused in the amplitude of the signal generated by the resistors R1, R2. As a result, a signal appears at an output terminal 12a of a differential amplifier. The result of discrimination is displayed by a light emitting diode 14 as the input to a level discriminator 13.