User Manual

Yealink Skype for Business HD IP Phones Administrator Guide
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3. Enter the minimum delay time for adaptive jitter buffer in the Min Delay field.
The valid value ranges from 0 to 300.
4. Enter the maximum delay time for adaptive jitter buffer in the Max Delay field.
The valid value ranges from 0 to 300.
5. Enter the fixed delay time for fixed jitter buffer in the Normal field.
The valid value ranges from 0 to 300.
6. Click Confirm to accept the change.
DTMF
DTMF (Dual Tone Multi-frequency), better known as touch-tone, is used for telecommunication
signaling over analog telephone lines in the voice-frequency band. DTMF is the signal sent from
the phone to the network, which is generated when pressing the phone’s keypad during a call.
Each key pressed on the phone generates one sinusoidal tone of two frequencies. One is
generated from a high frequency group and the other from a low frequency group.
The DTMF keypad is laid out in a 4×4 matrix, with each row representing a low frequency, and
each column representing a high frequency. Pressing a digit key (such as '1') will generate a
sinusoidal tone for each of two frequencies (697 and 1209 hertz (Hz)).
DTMF Keypad Frequencies:
1209 Hz
1336 Hz
1477 Hz
1633 Hz
697 Hz
1
2
3
A
770 Hz
4
5
6
B
852 Hz
7
8
9
C
941 Hz
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0
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D