CSN ETS 300 001 ed. 1

CSN ETS 300 001 ed. 1 This Access NET specifies the technical requirements (electrical, mechanical and method of signalling) and their associated compliance tests to be met by all TE at each of its ports provided for connection of the Public Switched Telephone Network (PSTN). This connection is effected at a standard analogue interface. This interface is characterised by a two-wire derived presentation using dc loop seizure and clear and low-frequency ac ringing signals below the speech passband.
Original English text of CSN EN Standard.
The price of the Standard included all amendments and correcturs.