PURPOSE: To surely discriminate the presence/absence of a cassette tape from a remote location and to detect open tape of a magnetic tape, by providing a discrimination section which detects the number of revolutions of a take-up reel and produces an output when the number of revolutions is a reference value or over.

CONSTITUTION: When a cassette tape is loaded in the recording or reproducing mode, an output of a frequency-voltage converting circuit 15 is lower than a reference voltage and no output is produced from a comparison circuit 16. Thus, even if an output from a discrimination circuit 14 is obtained, a gate circuit 17 is closed and no output appears at an output terminal 18. When no tape is loaded, an output from the circuit 15 is higher than the reference voltage, the comparison circuit 16 gives an output, the gate circuit 17 is opened and an output appears at the output terminal 18. Thus, the presence/absence of a cassette tape can be discriminated from a remote location.