BS 7940:1999

This standard applies to apparatus having an interface for the connection of Terminal Equipment (T.E.) intended for a Direct Exchange Line (D.E.L.) and specifies the performance requirements of the interface which make it appear to the attached T.E. that is interworking with a single 2-wire analogue PSTN D.E.L.Cross References:BS 6312-2-1:1994Telecommunications Act 1984BT SIN 249ETS 300659BT SIN 227BT SIN 242 BS 6312-1:1994BS 6305:1992ITU-T Recommendation P.53