This course is a study of the telephone system including facilities, key systems, and PBXs. Two-wire and four-wire circuits will be discussed along with E&M and SF signaling. Students will install, maintain, and troubleshoot several varieties of key systems and PBXs. Use of manufacture manuals to set up working systems is emphasized. Interfacing key systems to PBXs and PBXs to PBXs is included in the lab. This class also covers the theory of fiber optic transmission of communication signals. Subjects covered include light wave theory types and placement of cables, connectors, splicing, transmitters, and receive power budgets, etc. Students in lab will get experience in working with several types of glass fiber cable and associated electronics.