| 摘要 |
The present invention relates to a device for the switching from a recording mode to a reproducing mode of a reproducing head connected between first (A) and second (B) input terminals of a differential amplifier (12), the second input terminal being connected to a constant potential by way of a capacitor (C1) and to the output of the amplifier by way of a resistor (R2). The device comprises: a voltage ramp generator (C2, I3, S5), which is active following a recording; means (I2, S4, 16) for discharging the current from the reproducing head in proportion to the said ramp between the start (t4) of the ramp and a first threshold (V1) of the ramp; and means (S6) for switching the said resistor to a low value between the first threshold and a second threshold (V2) of the ramp. According to the invention, there is provision for means (Q1, Q2) of detection of the second threshold which ensure, in the vicinity of this threshold, gradual control of the said switching means. <IMAGE> |
