Specifications

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AS/CA S002:2010 COPYRIGHT
OCTOBER 2010
(d) Number Unobtainable (NU) Tone
(i) Frequency 425 Hz ±10 Hz.
(ii) Cadence 2.5 s on, 0.5 s off, ±10%.
5.3.4.2 Pre-answer levels
The level of audible supervisory tone (as specified in Clause 5.3.4.1)
measured during the ‘on’ period of the cadence when terminated
in a 600 Ω resistive impedance shall be in the range of –7 dBm to
–13 dBm, with a zero line length.
5.3.4.3 Post-answer tones
Tones transmitted after a call has been acknowledged by operator
intervention, or in accordance with Clause 5.3.5.3.2, by the CE
should be audibly and unambiguously dissimilar from PSTN pre-
answer tones (as described in Appendix A), unless the same
information is to be conveyed.
5.3.4.4 Return loss
The return loss requirements of Clause 5.4.3 shall be met when
supervisory tones, as specified in Clauses 5.3.4.1 and 5.3.4.2, are
applied to the line.
Note: A list of standard service tones is attached as Appendix A.
Compliance with Clause 5.3.4 should be checked by using the
method described in Clause 6.7.9.1.
5.3.5 Automatic operation
The requirements of Clauses 5.3.5.1 to 5.3.5.7 (inclusive) apply to CE
designed or intended to perform automatic functions or operations
(i.e. functions or operations which are not manually initiated,
performed or monitored).
5.3.5.1 Automatically seizing the line
CE shall not automatically seize the line for any purpose, other than
to—
(a) originate a call;
(b) answer a call;
(c) force a line into a busy state;
(d) detect the presence or absence of a distinctive dial tone in
accordance with the requirements specified in Appendix C; or
(e) automatically detect the state of the line as detailed under
Automatic Guard in AS/CA S003 [4].
Note: This Clause does not apply to CE during the initial 30 seconds of a
power up sequence or initial connection to the line.