Anordnung zur Prüfung der Teilnehmeranschlussleitungen einer digitalen Vermittlungseinrichtung

摘要

A device for testing line connections (5) at a telephone exchange (3) comprises a combined generator and comparator (9) for generating a bit sequence of pseudo-random type and for comparing a received bit sequence to a generated bit sequence. A generated bit sequence is through a line connection (5) forwarded to a telephone set (1) and back again to the generator and comparator (9), where the received sequence is compared to the forwarded one. The number of bit errors occurring in the transmission is a measure of the transmission quality of the connection. A selector device (11) selects one of several line connections which is to be tested, thus only one testing device being required for testing a number of line connections (5) which through the same pair (17) of one serial output line and one serial input line are connected to a telephone exchange (3).