Method for measuring the transhybrid loss of hybrid circuits of subscriber line circuits enabling 2-wire/4-wire transition

摘要

If the subscriber line circuits (TSCH) form part of a digital exchange (V), test signals in the form of PCM words generated by a PCM word generator (PCM-G) are switched according to the invention to the digital input of the subscriber line circuits in order to test the hybrid circuits (GA) contained in said subscriber line circuits, and the PCM words occurring thereafter at the digital output are evaluated in terms of a comparison with the PCM words generated by the PCM word generator. <IMAGE>