The 3785B Jitter Generator and Receiver is a dedicated jitter measurement system for testing and evaluating the performance of Bell digital transmission terminal and link equipment up to and including the third level (34368kb/s or DS-3) in the digital hierarchy. The 3785B can be used in production testing, field installation and maintenance of the Bell digital transmission system including PCM/TDM transmission over cable, radio, satellite, and fiber optic links. The Jitter receiver offers six types of measurement.