ÿWPCL ûÿ2BJ|xÐ ` ÐÐÌÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿH øÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÌÐÐ °°°è ÐÑ Âx„|ü@Ž ÑÐ Å°6Ø'°6Ø'Å Ð4.ÂXHÂÓÓÃÃProposed amendments to Recommendation 0.62ÄÄÆÆ Áà*ÁSOPHISTICATED EQUIPMENT TO MEASURE INTERRUPTIONƒ Áà4ÁON TELEPHONE©TYPE CIRCUITS ƒ ÁHÁ ÁHÁÃÃAmendÄÄ section 2.3.1 to read as follows: Ð ð Ð"2.3.1 Á  ÁThe detector shall respond to a test signal of 2 000 Hz ÃÃ+ÄÄ 100 Hz (see also ÀÀ 5)." ЀÐÃà         ÄÄ ÐÐ* The loss shall continue to increase above 6 000 Hz at a rate of not less than 12 dB per octave until it reaches a value of 60 dB. The loss at higher frequencies shall be at least 60 dB. ÁHÁÃÃDeleteÄÄ ÀÀÀÀ 2.3.3 and 2.3.3.1. ÁHÁÃÃInsertÄÄ new ÀÀÀÀ 2.4, 2.4.1 and 2.4.2 as given below: "2.4 ÁHÁInput impedance (frequency range 300 Hz to 4 kHz) ÁHÁ©Á  ÁBalanced, earth free ÁHÁ©Á  ÁInput longitudinal interference loss ÃÃ>ÄÄ 46 dB 2.4.1ÁHÁTerminating impedance (other impedances optional) 600 ohms ÁHÁ©Á  ÁReturn loss ÃÃ>ÄÄ 30 dB 2.4.2ÁHÁHigh impedance approx. 20 kohms ÁHÁ©Á  ÁBinding loss across 300 ohms ÃÃ<ÄÄ 0.15 dB". ÁHÁÃÃRenumberÄÄ the existing ÀÀÀÀ 2.4.2.1 and 2.4.2.2 to "ÀÀÀÀ 2.4.3 and 2.4.4". ÁHÁÃÃReplaceÄÄ section 3 with the following text: "3.ÁHÁÃÃDisplay of measurement resultsÄÄ 3.1ÁHÁÃÃInterruption countersÄÄ ÁHÁThe detected interruptions shall be divided into the following time categories for recording purposes: ÁHÁ1)Á   Á0.3 (0.6) ms © 3 ms (optional, see note), ÁHÁ2)Á   Á3 ms © 30 ms, ÁHÁ3)Á   Á30 ms © 300 ms, ÁHÁ4)Á   Á300 ms © 1 min, ÁHÁ5)Á   Á1 min and over (optional). ÁHÁFacility for adjusting to other time groupings may be provided at the option of the administrations. The count shall be presented on a visual display. ÃÃNoteÄÄ © The value of 0.6 ms applies to the 1 020 Hz test tone. 3.2ÁHÁ ÃÃRelative duration of interruption events (optional)ÄÄ ÁHÁTo allow an easier estimation of data transmission errors which may result from interruptions, the instrument shall provide means to calculate and indicate the relative duration of interruption events. This quantity is the ratio of the time where the test tone is below a designated threshold to the total measurement time. Interruptions between 3 ms and 1 minute shall be taken into account. Results shall be indicated in a range 1 x 10Ãé1ÄÄ to 1 x 10Ãé8ÄÄ. 3.3ÁHÁÃÃSeconds containing an interruption (optional)ÄÄ ÁHÁAs a further option, the instrument shall provide means to calculate and indicate the percentage of seconds containing one or more interruptions of a duration ÃÃ>ÄÄ 3 ms. Results shall be indicated in a range 0 to 100% with one digit after the decimal point. 3.4ÁHÁÃÃPower failureÄÄ ÁHÁIn the event of a power failure any loss of measurement results should be clearly indicated on a display for later observation." ÁHÁÃÃAddÄÄ a new section 5 to read as follows: "5.ÁHÁÃÃSimultaneous measurementsÄÄ ÁHÁThe measurement of interruptions may be provided in an instrument which also makes measurements of other transient impairments, e.g., amplitude and phase hits. A test signal frequency of 1 020 Hz +2 ©7 Hz may be used to facilitate the integration of several measurements of transient phenomena in such a combined instrument. In all other respects, the measurement of interruptions shall be in accordance with the principles of this Recommendation." ÁHÁThe X©axis of Figure 1/0.62 shall be labelled as shown below: Áà8JÁInterruption lengthƒ Áà8SÁƒ Áà8MÁFIGURE 1/O.62ƒ Áà8SÁƒ Áà8BÁÃÃProbability curve for the detectionÄă Áà8JÁÃÃof an interruptionÄă