首页>
外国专利>
Calling telephone line identification circuit - successively applies positive and negative test potentials to locate potentials retransmitted by calling appts.
Calling telephone line identification circuit - successively applies positive and negative test potentials to locate potentials retransmitted by calling appts.
展开▼
机译:呼叫电话线识别电路-连续施加正负测试电势以定位通过呼叫设备重新传输的电势。
展开▼
页面导航
摘要
著录项
相似文献
摘要
The calling subscriber lines retransmit a potential applied to them. A first identification process identifies the incoming group containing the caller, and a second identification process narrows it down precisely. The potential in each subscriber line is retransmitted through switching diodes. A first positive test potential is applied to row selector frame wires to which the lines are connected. The column wire receiving the test potential is selected. A negative second test potential is applied, and a row frame wire receiving the second potential is selected. Thus the group and position of a calling line is identified.
展开▼