| 摘要 |
PURPOSE:To eliminate time and labor for switching by automatically switching a busy contact transfer system and an idle contact transfer system. CONSTITUTION:In transmission devices 2, 3 for repeating a call signal from a switchboard 1 to the switchboard 4 (busy contact transfer system) or mobile communication equipment 5 (idle contact transfer system), a call signal repeater circuit is constituted of communication system discrimination circuits 21, 31 to discriminate whether the call signal from the switchboard 1 is dial signal for the switchboard or a pulse signal for mobile communication, polarity switching circuits 22, 32 for switching the signal polarity of a transmission line side, and a timing circuit 33. In the busy contact transferring system, the outputs of the communication system discrimination circuits 21, 31 are a state '0', and relays 222, 322 are non-operative, and a contact is turned into the state of a full line. In the idle contact transferring system, the outputs of the communication system discrimination circuits 21, 31 are the state '1', and the relays 222, 322 are operative, and the contact is turned into the state of a dotted line. |
