| set of equipment kept in the CCITT Laboratory comprising:|
a telephone transmission system subdivided into sending system, line and receiving system;
a centralized apparatus for the supply of ambient noise and intercommunication facilities;
a calibration equipment arranged to facilitate the proper maintenance of the set of equipment
NOTE 1 – The ARAEN is described in the CCITT Recommendation P41 from the Volume V of the Yellow Book, 1981.
NOTE 2 – The ARAEN is used in the constitution:
of the new fundamental system for the determination of reference equivalents or NOSFER;
of the reference system for the determination of AEN or SRAEN.