| 摘要 |
PURPOSE:To eliminate the need for a subordinate office operator to wait until a free channel is captured by temporarily storing a dial number at each subordinate office for subordinate office calling, and transmitting the dial number after a free channel is captured. CONSTITUTION:A subordinate office SS has a master telephone set TEL1, a subordinate telephone set TEL2, and a private branch exchange PBX. When a telephone set TEL sends an off-hook signal, a dial tone is supplied from a signal generating circuit SG, and dial origination is performed, dial pulses are discriminated by a control circuit CTC and when they show an office number other than its number, a calling control signal is generated immediately and the dial signal is stored in a memory successively. Once the calling control signal is generated, a free channel is captured by detectong a free line signal to transmit a call signal to a master office over the channel, and a break of the free line signal which corresponds to the call signal is confirmed to transmit said stored dial signal to the master office. |
