| 摘要 |
In a signal device for a telephone, a bridge rectifier circuit is connected between the user-lines (L1) (L2), and a melody-memorized IC is operated by an output of the rectifier. The melody sound of the IC sounds with a receiver (R) through the amplifier circuits(TR1, TR2, TR3), and the contact points of the hook switch are converted by raising the hand-set. The rectifier output is charged by the condensors (C1-C), and which also server as the power source for the IC and the amplifier circuit.
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