PURPOSE: To set accurately a cassette to a pack guide, by providing a power supply application switch to the pack guide part to apply the power supply to a motor after detecting that the cassette is set into the packguide.

CONSTITUTION: A power supply application switch SW1 and a power supply holding switch SW2 are set in parallel between a power supply E and a motor M. The supply E is applied to the motor M if either one of two switches is connected. At the same time, a loading/unloading driving circuit S is set between the switches SW1, SW2 and the motor M. The circuit S is connected to an automatic loading mechanism O to control the application of the supply E to the motor M in a traveling mode of tape or in a loading start mode of cassette when the cassette loading is over.