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The TDS/DTR card Page 245 of 544
Option 11C and 11C Mini Technical Reference Guide
Table 85
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