PURPOSE: To attain smooth communication without interruption of communication, by providing a means detecting a failure of a master modulator and disconnecting the master modulator instantly with this alarm signal from this means.
CONSTITUTION: A failure detecting circuit 6 has a function detecting a failure in the output of the master modulator 1, a failure in frequency and interruption of a base band signal at the inside of the master modulator 1. When this detecting circuit 6 detects the failure in the master modulator 1, the alarm signal goes and a disconnecting circuit 7 disconnects the master modulator 1 from a line instantly. Thus, a signal modulating the base band signal at a slave modulator 1' is transmitted to an opposite station via a circulator 5 and the communication is performed smoothly without interruption of communication.
NOGUCHI YOSHIFUMI
IWATA KEIJI
FUJITSU LTD
| JPS5693435A | 1981-07-29 |