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• CCITT Rec. O.22 (11/1988) – CCITT AUTOMATIC TRANSMISSION MEASURING AND SIGNALLING TESTING EQUIPMENT ATME No. 2
• 1 General
• 2 Kinds of measurements and tests
• 3 Equipment for making transmission measurements and processing the results
  • 3.1 Absolute power level measurements
  • 3.2 Noise measurements
  • 3.3 Signal-to-total-distortion ratio measurements
  • 3.4 Echo canceller testing system (ECTS)
  • 3.5 Digital loopback tests
  • 3.6 Adjustment results
  • 3.7 Recording and presentation of output
  • 3.8 Remeasurement and retest arrangements
• 4 Method of access
  • 4.1 In general, access arrangements will conform to Recommendation M.560 [3].
  • 4.2 Outgoing international exchange
  • 4.3 Incoming international exchange
• 5 Operating principles
• 6 Signalling system testing and transmission measuring procedure-director to responder
  • 6.1 Establishment of connection and signalling test sequence
  • 6.2 Busy flash test
  • 6.3 Transmission measuring procedure and exchange of information between directing and responding equipments
  • 6.4 Description of transmission measuring cycles
  • 6.5 End-of-programme procedure
  • 6.6 Description of Layer 2 transmission measuring cycles
  • 6.7 Description of echo canceller testing cycles
  • 6.8 Echo canceller test timing and error considerations
  • 6.9 Responder digital loopback test
  • 6.10 System supervision
• 7 Description of tests to digital loopback test lines
  • 7.1 ...
  • 7.2 Analogue tests on all circuit types
  • 7.3 Digital tests on wholly digital circuits
• 8 Programming
• 9 Specifications for transmission measuring apparatus and for disabling tones and locking tones
  • 9.1 Absolute power level measuring device
  • 9.2 Noise and total distortion measuring apparatus
  • 9.3 Disabling and locking tones
  • 9.4 ECTS sending apparatus of the directing and responding equipment
  • 9.5 ECTS receiving apparatus of the directing and responding equipment
  • 9.6 ECTS command signals exchanged between the directing equipment and the responding equipment
  • 9.7 Digital pattern generator and detector
  • 9.8 Test pattern detector
• 10 Calibration
  • 10.1 Built-in calibration
  • 10.2 Self-check
• 11 Optional arrangements
  • 11.1 Automatic start
  • 11.2 Timed automatic selection of particular circuits or groups of circuits
  • 11.3 Automatic repeat attempt
  • 11.4 Switching pad test
  • 11.5 Interruption and instability during level measurements
  • 11.6 Nonavailability of responding equipment
• ANNEX A (to Recommendation O.22) Sensitivity of the signalling receiver