| 摘要 |
Message signalling device for telephone installation with analogue sets and set equipped for this purpose. The subjects of the invention are a device for signalling by luminous means, for telephone installation whose subscribers are furnished with analogue sets as well as the sets equipped for this purpose. Each relevant telephone set 4 is equipped in parallel, on the one hand with a message lamp 59 in series with a resistor 60, and, on the other hand, with a capacitor 61 at the output of the rectifier bridge 51 of the set. The message signalling is carried out by action of the control unit 3 of the central equipment on the call-signals injector 36 assigned to the set, so as to cause it to transmit clock signals which differ from the clocked call signals by the shortest duration of the signal transmission phases and which allow the lamp to be lit. <IMAGE>
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