| 摘要 |
PURPOSE:To shorten the time required for confirmation of a signal receiver at the opposite side when the new and old type signal receivers are used, by superposing a call signal corresponding to the new type receiver on the call signal of the old type receiver, and transmitting these signals. CONSTITUTION:In case two signal receivers of new and old types are used, the call signals A and X are transmitted at one time to the receiver at the opposite side via a telephone circuit 4 and by a command given from a transmission control part 11 of a signal transmitter 1. In the case of the new type receiver, both signals A and X are deteced and an answer signal C is transmitted based on the detection of the call signals. Thus the part 11 confirms that the new type receiver is used at the opposite side and then transmits the data in the new type transmission mode. In the case of the old type receiver, only the signal A is received and detected and then an answer signal B is transmitted to confirm the old type receiver. Thus the data is transmitted in the old type transmission mode. |
