Identification of digital impairments in a voiceband channel

Some recently developed analog transmission tests and some familiar analog transmission tests that can give the end user the ability to report specific digital impairments to the exchange carrier or interexchange carrier are discussed. Trouble reports with this specific digital impairment identification can be resolved more rapidly. It is shown how analog testing techniques for slips, bit errors, digital pads, digital timing jitter, and adaptive differential pulse code modulation (ADPCM) permit identification of digital impairments or reduced allocation of bits ranging from unambiguous signatures to probable cause