
Microsoft Lync Edition Administrator’s Guide for SIP-T2_Series and T4_Series IP Phones
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2.
Enter the desired characters in the Call Number Filter field.
3.
Click Confirm to accept the change.
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 IP phone to the network, which is generated when
pressing the IP phone’s keypad during a call. Each key pressed on the IP 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
1447 Hz
1633 Hz
697 Hz
1
2
3
A
770 Hz
4
5
6
B
852 Hz
7
8
9
C
941 Hz
*
0
#
D
DTMF digits are transmitted using the RTP Event packets that are sent along with the
Summary of Contents for Yealink SIP-T48G
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Page 12: ...Microsoft Lync Edition Administrator s Guide for SIP T2_Series and T4_Series IP Phones xii ...
Page 19: ...Product Overview 7 Admin User configuration mode 802 1X authentication ...
Page 20: ...Microsoft Lync Edition Administrator s Guide for SIP T2_Series and T4_Series IP Phones 8 ...
Page 248: ...Microsoft Lync Edition Administrator s Guide for SIP T2_Series and T4_Series IP Phones 236 ...
Page 266: ...Microsoft Lync Edition Administrator s Guide for SIP T2_Series and T4_Series IP Phones 254 ...