Automatic switch-off for record player - senses absence of amplifier output to switch off motor and amplifier, and has motor to rotate disc

摘要

An automatic electronic circuit simultaneously stops the rotation of a record player table and also switches off the amplifier when the last groove is reached. The circuit detects the head output to eliminate mechanical elements. A record player comprises a power supply circuit (9) and an amplifier (10) connected to the pick up assembly (8) on the arm (7). The record table is rotated by a motor (11) and the sound output is delivered by a loudspeaker (4). An electronic switch circuit (12) between the power supply output and the motor is driven from the head output. This senses when there is no output and when there is a repetitive signal whose period is equivalent to that of a rotating record. A switch (13) permits either manual or automatic operation of the switch-off.