Monitored private telephone system - has transfer device and distributor for traffic signalling and power distribution monitoring

摘要

The private telephone system, for traffic signalling and power distribution monitoring etc., connects out-stations with central control via information channels carrying voice and control signals. The information channels carrying voice signals are connected directly to the input of a transfer device whose output is connected to the distributor for serving the peripheral units. The transfer device is first connected via the distributor to a calling subscriber and then, in a second process, to the called subscriber. The advantage lies in not needing two voice channels between central control and out-stations for one link between two subscribers and in limiting the busy time of the voice channel to a min.