Channel unit

Abstract

Abstract PURPOSE:To make the execution of a test possible independently of the use state of a circuit by connecting a subscriber circuit selector switch and a trunk circuit selector switch to an alternative path and connecting an incoming line selector switch and an outgoing line selector switch to the tone generation circuit side and the tone detection circuit side respectively. CONSTITUTION:In case that subscriber circuit 3 connected to the incoming line which is a test object is connected to trunk circuit 4 through switch network 5, subscriber circuit selector switch 10 and trunk circuit selector switch 12 are switched to the alternative path 8 side. Next, incoming line selector switch 14 and outgoing line selector switch 15 are switched to the tone generation circuit 6 side and the tone detection circuit 7 side respectively, and the incoming line and the outgoing line which should be tested by circuit 5 are connected to form a bus from circuit 6 to circuit 7. In this case, when circuit 5 is normal, tone signals can be detected by circuit 7. As a result, the test can be performed independently of the use state of circuits 3 and 4.

Inventors

• 👤 Shigeru Aoyama

Bibliographic Details