| 摘要 |
PURPOSE:To simplify the operation as well as eliminate the throw-in of the excessive coins, by providing the means to open the loop circuit to the telephone office and the means to repeal the opening of the loop circuit after storage of the coins each in addition to the hook switch FS. CONSTITUTION:In case a successive calling is given to several called subscribers, the calling subscriber pushes the recall button A while picking up the handset after the end of the 1st call. In this case, if the residual coins exist, the contact B is under operation. And the loop circuit opens by the operation of the button A with the release secured for the office switchboard. With the release of the button A, the loop circuit is completed again. And the dial tone is sent from the office, and thus the caller can start immediately an operation for selection of the called subscriber. The 2nd calling charge is stored following the residual coins existing at the end of the 1st call. If the accumulated coins are all stored, the contact B has already the release. Thus the loop circuit to the office has no opening even with the operation of the button A to prevent the ineffective recall action of the office switchboard. |
