General Dynamics R2670 Series - Table B-1. Standard DTMF TONES; Table B-2. DTMF Frequency Coding

Appendix B
TONE AND CODE SPECIFICATIONS
Table B-1. Standard DTMF Tones
Tone Group Standard Dtmf (Hz)
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
697
770
852
941
1209
1336
1477
1633
Table B-2. DTMF Frequency Coding*
Low Group Tone
(Hz)
High Group Tone
(Hz)
Key
697 770 852 941 1209 1336 1447 1633
1
2
3
A
4
5
6
B
7
8
9
C
*
O
#
D
































B-1