| 摘要 |
<p>PURPOSE:To measure a transmission line state without deteriorating the measurement accuracy and without lowering the transmission efficiency of the whole system by outputting measured data only in the case a carrier ON time is long. CONSTITUTION:After measuring each transmission line data, it is averaged by an averaging circuit 7 so that necessary accuracy can be secured, respectively, and averaged data is outputted to a memory circuit 8 through a switching circuit 6. This switching circuit 6 is turned ON only in the case a carrier detecting(CD) signal is turned ON exceeding some determined time. Therefore, only the data averaged enough by the time when the accuracy can be secured is stored in the memory circuit 8, or the data stored in the previous time is rewritten to new data and updated. This memory circuit 8 has stored areas in accordance with each slave MODEM, the data is stored in accordance with each of them and the stored data is outputted to a display part contained in other device than the MODEM, or the MODEM. In such a way, a transmission line state can be observed with high accuracy, and also, efficiently.</p> |
