W+G PFA-35 is a multi-purpose instrument designed for commissioning, maintenance and troubleshooting on digital networks. It is used to carry out both framed and unframed tests on a wide variety of equipment such as primary multiplexers, X.50 multiplexers, digital cross connects, automatic protection switches and circuits operating at speeds from 50 bit/s to 2048 kbit/s. WG PFA-35 can be configured as a DCE as well as a DTE; this allows a data circuit to be taken out of service and tested in sections so that a fault can be isolated to a specific part of the circuit. The WG PFA-35 has 4 built-in interfaces which can be further supplemented by means of cable adaptors allowing testing at 7 different types of interface.