to which the stop sense signal line 64 is connected a tape run signal in line 62 is operative through transistor 116 to energize a tape run control relay coil 118 causing its normally open relay switch 120 to close in order to apply a signal to the tape transport mechanism through start signal line 122 operation of the tape transport mechanism is thereby initiated for both the recording and playback operations when the sensing head 114 detects the stop signal on the tape the stop sense signal in line 64 is operative through the logic switching module 36 to supply a stop signal in line 66 which is operative through transistor 122 to energize the stop control relay coil 124 energization of the relay coil 124 closes its normally open relay switch 126 in order to apply a negative signal to the stop signal line 128 to thereby interrupt operation of the tape transport mechanism 104 recording operation is initiated by a signal in line 50 which is operative through transistor 130 to energize the record control relay coil 132 relay switch 134 is thereby actuated in order to connect the positive voltage line 38 to the indicator 68 through line 70 in order to visually signify recording operation at the same time relay switch 136 as shown in fig3 is actuated to apply voltage from the positive voltage line 38 through line 138 to recording amplifiers 140 and 142 thereby rendering these amplifiers operative the alerting signal from signal generator 42 is applied through line 46 to the input of recording amplifier 140 the output of which is connected to the tape head 108 for recording the alerting signal.