Specifications

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AS/CA S002:2010 COPYRIGHT
OCTOBER 2010
Compliance with Clause 5.4.2.4.2 should be checked by using the
methods described in Clauses 6.7.9.1, 6.7.9.2, and 6.7.9.5(b) with R in
Clause 6.7.9.2 and Figure 23 set to 135 Ω.
5.4.3 Impedance
5.4.3.1 OFF-LINE state
The impedance presented by the CE in the OFF-LINE state should be
greater than 15 kΩ over the range 300 Hz to 3400 Hz.
5.4.3.2 Hold state
The impedance presented by the CE in the hold state shall have a
return loss greater than 10 dB over the range 300 Hz to 600 Hz and
greater than 15 dB over the range 600 Hz to 3.4 kHz against the test
network shown in Figure 5.
Note 1: It is recommended that CE requiring a higher level of impedance
matching may additionally incorporate a 600 Ω network as a
switchable option.
Note 2: It is recommended that CE presents this value of impedance as
early as possible after the application of a loop, but no later than
1 s. This will allow Carrier or carriage service provider network
equipment that adapts to the CE/line impedance to do so in a
timely manner.
Compliance with Clause 5.4.3 should be checked by using the
method described in Clause 6.7.2.
5.4.4 Impedance balance
The impedance balance about earth of the CE shall be greater
than 46 dB over the frequency range 50 Hz to 3.4 kHz. This test is to
be applied with respect to the TRC terminal and protective earth
termination, separately and connected together when either or
both of these terminations are provided.
Compliance with Clause 5.4.4 should be checked by using the
method described in Clause 6.7.3.
5.4.5 Noise performance
The following requirements for noise generated by STS CE when
measured across a 600 Ω port termination (with other equipped
ports properly terminated) are to apply when the STS CE is in the
ON-LINE state and not transmitting signals:
(a) Mean noise power shall not exceed—
(i) –62 dBmp (Psophometric), measured using a device
compliant with ITU–T Rec. O.41 [18]; and
(ii) –37 dBm (unweighted), measured using a device with a
uniform frequency response over the range 30 Hz to
20 kHz.