Nortel Circuit Card Installation Manual page 897

Table 279
NTAK03, NTDK20, and NTDK97 A-Law tones and cadences (Part 6 of 9)
Tone # Frequency (Hz)
167 1700
168
169
170 1400
171
172
173
174 reserved
175
176
177 1020
178 1800
179 1400
180
181 1400
182 1800
183
184
185
186 1880
187
dB below
overload
440
380
820
850
420
420
420
950
950
470
940
400
The TDS/DTR card
Precision
Ringing
Tones
-19 ÷
-14 ÷
-8 ÷
-32 ÷
-7
-8
-32
-6
-2
-13
-17
-23
-29
-29
-29
-22
0
0
0
-22
Circuit Card
Page 897 of 906
DTMF
Digits MF Digits
P
1
2
3
4
5
6
7
8
9
0
*
#
F0
F
I
Description and Installation