BS PD 6562:1992 English Secure PDF English Printed Edition A draft amendment to BS 6789-3.1:1985 'Apparatus with one or more particular functions for connection to the British Telecommunications public switched network. Part 3 . Apparatus with auto-calling, auto-answering and auto-clearing facilities. Section 3.1. Specification for auto-calling facilities'

standard published 10/31/1992 by British Standards Institution