How many DTMF tones are there?

Related questions

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2. What is DTMF encoder?
3. What does DTMP mean in texting?
4. What are the tones called when you press a key on your telephone?
5. What is a DCS code?
6. Can you still use old rotary phones?
7. What is DTMF detection?
8. What does DTMF mode mean?
9. What is DTMF circuit?
10. What is the difference between tone and pulse dialing?

Tags

1. #number
2. #dialing
3. #frequencies
4. #instance
5. #touch
6. #refered
7. #tones
8. #represented
9. #sounds
10. #multiple