The Keysight / Agilent / HP 3784A is a portable error performance/jitter test set, offering standard telecom interfaces at 704 kb/s, 2, 8, and 34 Mb/s, with the option of codirectional interfaces at 64 kb/s and V.11 interfaces for testing X.21 leased circuits. In addition, it has binary TTL/ECL interfaces for measurements up to 50 Mb/s, using the internal clock synthesizer.

HP 3784A is easy to use with measurement presets, automatic receiver setup and error performance pass/fail thresholds. Automatic jitter tolerance and transfer plotting routines are provided for fast accurate testing up to and beyond CCITT limits. Through-data mode allows jitter to be added to a structured signal for jitter tolerance testing of demultiplexers.