| 摘要 |
647,765. Intercommunication systems. LEGERTH, K. I. B. Dec. 11, 1946, No. 36607. Convention date, Jan. 24. Drawings to Specification. [Class 40 (iv)] In an intercommunication system having at least four stations each provided with a loudspeaker serving as both transmitter and receiver and with a key for calling each of the other stations, calls are set up over a number of link circuits less than the number of stations, each of which comprises an amplifier and a group of relays. A common allotter is taken into use by the operation of the start key of a calling station and operates the relay group of a selected idle link circuit to connect the loudspeaker of the calling station to the output side of the amplifier. Depression of the calling key corresponding to the wanted station then operates the relay group to connect the loudspeaker of the wanted station to the input side of the amplifier. Re-operation of the start key controls the changing-over of the connections to the amplifier to permit the calling party to speak. Release is under the control of the calling party and is initiated by operation of the station's restore key. Two-way amplifiers may be used and directional switching is then not required. |
