Chapter:ChapName1-2 7920-A2-GB20-10August 1997Hotwire Model 7925 Standard Features G.703 interface Meets the requirements of repeaterless E1 transmission on loops exceedingstandard specifications (up to 10 km on a 0.9 mm wire) Automatic detection and compensation for inverted pairs and swappedloops – significantly simplifies installation Local and remote alarm surveillance and performance monitoring Local and remote E1 and HDSL performance monitoringYou can order HotWire 7924 and 7925 products as standalone units(7924-A1/7925-A1) or as nest-mounted circuit card assemblies (CCAs)(7924-B1/7925B1) that fit in the HotWire 7900 Nest. This guide describes theinstallation and maintenance procedures for the nest-mounted CCAs,Models 7924-B1 and 7925-B1. SeeProduct-Related Documents inAbout ThisGuide for information on user manuals for the standalone units.HotWire Model 7924 Typical ConfigurationsHotWire Model 7924 termination units can be used in campus applications wherelong loop distances normally require the campus to contract with the localtelephone exchange carrier to deliver private-line services across the campus.Figure 1-1 shows a central-site application with a HotWire 7900 Nest containingHotWire Model 7924 Nest Card Termination Units. Each nest card terminates asingle subscriber line in the central site. Each line is then converted to a DSX-1interface for connection to other central-site equipment, such as a digitalcross-connect system (DCS).PBXDSX-1 UnitRouterDSX-1DCSMgmtStation7900 NestNestCardsV.35 UnitV.35MultiplexerDSX-1 UnitDSX-1Telco 2- or 4-wirefacilities tocustomer premisesCustomer PremisesCentral Site97-15294Figure 1-1. T1 Extension to Customer Premises