| 摘要 |
PURPOSE:To easily recognize it as power supply interruption when a power supply of an opposite station is interrupted by sending an interrupt signal to a transmission line via a hybrid transformer and allowing an interruption signal detection circuit and a guard circuit of a receiver side to detect an interruption signal so as to raise a power supply interrupt alarm. CONSTITUTION:The system is provided with a power supply monitor circuit 2 monitoring power supply interruption, a capacitor 6 receiving supply of charge by power supply, a diode 4, an interrupt signal generating circuit 7, and a hybrid transformer 8 coupling an output of a main signal transmission circuit 3 with an output of the interrupt signal generating circuit 7. Then a voltage charged across the capacitor 6 acts like a power supply circuit tentatively at interruption of power and an interrupt signal outputted from the interrupt signal generating circuit 7 is sent to an opposite station through the hybrid transformer 8. On the other hand, the interrupt signal and an output of an interrupt signal detection circuit 10 and a guard circuit 11 are ANDed at a receiver side to output a power supply interrupt alarm. Thus, in the case of interruption of the power supply of the opposite station, the power supply interruption is easily recognized. |
