"Digital Terminal Wallmount circuit assignment card?

[JJWalecka]

What is the function of a Digital Terminal 2 Slot Wallmount circuit assignment card?

 

[EV607797]

Up to two digital circuits (usually T1 circuits) are brought in by the telephone service provider from the street and are terminated on one of these shelves. There are two card slots that contain a card that provides line conditioning and test/diagnostic capabilities for the service provider to use to troubleshoot or finger point. The customer plugs their equipment into the jacks on the back of the unit.