The Agilent / HP 37744A is a small, rugged, and easy-to-use SONET tester for applications up to 155 Mb/s. It provides a low-cost solution for the generation and analysis of the section line and path overhead on structured 52-Mb/s or 155 MB/s SONET signals. The tester is intended for applications in SONET circuit installation and maintenance, as well as for circuit monitoring in central offices.