Specifications

- 31 -

AS/CA S002:2010 COPYRIGHT

OCTOBER 2010

Compliance with Clause 5.5.1.9(b) should be checked by using the

method described in Clause 6.7.8.

envelope of each tone of each digit, measured between 10%

and 90% of full amplitude, shall be within 5 ms with the CE

connected to all line lengths between 0 km and 4.2 km using

0.40 mm cable terminated in 600 Ω.

Compliance with Clause 5.5.1.9(c) should be checked by using the

methods described in Clauses 6.7.8 and 6.7.9.

(d) Distortion The total distortion products (measured as

harmonics or intermodulation) shall be at least 20 dB below

the level of the lower power fundamental frequency when

measured at the line terminals of the CE.

Compliance with Clause 5.5.1.9(d) should be checked by using the

method described in Clause 6.7.8.

(e) Timing The timing for automatically and/or repertory dialled

DTMF signalling is to be as follows:

(i) The minimum duration of the DTMF burst representing

each digit shall be 50 ms.

(ii) The minimum interval between the transmission of digits

shall be 70 ms and in no case shall it exceed a maximum

period of 3 s unless due to a programmed pause.

Note: It is recommended for post answering DTMF information signalling

that the digit duration should be a minimum of 100 ms.

Compliance with Clause 5.5.1.9(e) should be checked by using the

methods described in Clauses 6.7.8 and 6.7.9.

(f) Line termination characteristics During DTMF signalling over

the frequency range 600 Hz to 1660 Hz for DC line conditions,

provided by DC feed resistances between 400 Ω and 2300 Ω,

the source impedance of the CE shall have a return loss

greater than—

(i) 7 dB with respect to 600 Ω; and

(ii) 15 dB with respect to the complex impedance as shown

in Figure 5.

Note: To facilitate the measurement of this requirement, equipment

suppliers should provide details of the test configuration for the CE.

Compliance with Clause 5.5.1.9(f) should be checked by using the

method described in Clause 6.7.2.