| 摘要 |
<p>An alphabet code converter (ACW1) arranged at the transmitting end of the digital transmission system generates output signals in accordance with the code alphabets provided, which signals only have a certain maximum number of equal-valued elements, for example zero bits. For the purpose of no-address fault location, control signals are provided which cannot occur during normal operation and which have a relatively large number of identical code elements following one another directly. For this reason, an alphabet code converter (ACW1) is proposed which can be switched (S1) during the fault locating operation and which generates a ternary loop closure signal from a binary loop closure signal. The system can be used for digital transmission links, particularly for PCM signals, having a relatively large number of regenerative repeater stations. <IMAGE></p> |
