The TDS/DTR card Page 875 of 894
Circuit Card Description and Installation
Tones and cadences
The following tables give the tones and cadences provided by the NTAK03
TDS/DTR card.
Table 273
NTAK03, NTDK20, and NTDK97 µ-Law tones and cadence (Part 1 of 6)
Tone #
Frequency
(Hz)
dB below
overload
Precision
Ringing
Tones
DTMF
Digits
MF Digits
1 350/440 -23/-23 ÷
2 (533 + 666) x 10 -23/-23 ÷
3 440 -23 ÷
4 350/440 -19/-19 ÷
5 440/480 -25/-25 ÷
6 480 -23 ÷
7 480/620 -30/-30 ÷
8 1020 -16 ÷
9 600 -23 ÷
10 600 -16 ÷
11 440/480 -22/-22 ÷
12 350/480 -23/-23 ÷
13 440/620 -24/-24 ÷
14 940/1630 -12/-10 P
15 700/1210 -12/-10 1
16 700/1340 -12/-10 2
17 700/1480 -12/-10 3
18 770/1210 -12/-10 4