PURPOSE: To prevent recording due to misoperation during reproduction, by simplifying the construction and making the operation of a recording/reproduction changeover switch easy, through the combination of a gear mechanism, cam mechanism and a rotary arm.

CONSTITUTION: At the recording where a recording operation plate 8 is depressed, a projection 3c of a rotary arm 3 and a recess 6c of a recording arm 6 are latched, the arm 3 presses the arm 6 to operate a recording/reproduction switch 30. At the reproduction where a reproduction operating plate 7 is depressed, a lock arm 4 releases the locking of an intermittent gear 2 to gear the intermittent gear with a driving gear 1 for the revolution at a prescribed angel. A cam 2a rotates the arm 3 clockwise and advances a head chassis 23 to the reproducing position at a latch 3e. Even if a recording operation plate 8 is desired to be depressed, it can be made disable through the contact of one end 6a of the arm 6 with the arm 3.