Abstract: A system is disclosed for intelligently providing suggestions for solving problems encountered during installation and testing of complex electronic circuitry. A plurality of first outputs provide indications of non-selectable conditions of the system, such as conditions related to power supplies. A plurality of second outputs provide indications of conditions of signals coupled to the system, and a plurality of third outputs provide indications of selectable parameters, such as switch positions. These indications and conditions are monitored for incorrect conditions and are polled in an order determined by importance of the condition with respect to operation of the system. Responsive to an incorrect condition or indication being polled, the polling process is halted and a message is generated indicating how the incorrect condition or indication may be corrected.

Abstract: A telecommunications line test system wherein a digital telecommunications network is electronically sectionalized via at least one master test unit in combination with at least one remotely addressable field loopback unit whereby the defective line section is isolated by progressively looping back test data as transmitted from a master test unit. Each field loopback unit, when properly addressed, will loopback to both the near side and the far side of the line so as to enable a given loopback unit to be reset (inactivated) from either side of the line.

Abstract: A sample of a normal data communications stream producing an error is thereafter employed via a loop back arrangement as a test sample data stream for error detection.