| 摘要 |
PURPOSE:To ensure an accurate monitor for the miscontrol and the malfunction, by setting the characteristic variation of the equalizer and then monitoring the working condition of the equalizer by the electric signal. CONSTITUTION:Both the setting and reading clocks for the equalizer characteristics are transmitted by frequency f1 to variable equalizer RCE which receives the remote control from the end office. At the same time, the control data of the digital signal is transmitted by frequency f2. And frequencies f1 and f2 are integrated at the integrating circuit, and the time constant of the integration is set to a proper value. Thus gate SRG opens, and meanwhile the signal of f2 is taken successively into shift register SR to set circuit network EQN to the desired characteristics. The setting condition of equalizer RCE is turned into the series signal again by parallel-series signal converter PSC, and the monitor signal (SV tone) particular to each variable equalizer and generated from monitor signal generator SVO is modulated at mixing gate G and by the next f1 signal sent from the end office. The modulated monitor signal is then transmitted to the end office via transmission line LL. |
