Yealink SIP-T33P Administrator's Guide

Administrator’s Guide for SIP-T2 /T3 /T4 /T5 /CP920 IP Phones
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DTMF Keypad
The DTMF keypad is laid out in a 4×4 matrix, with each row representing a low frequency, and each column rep-
resenting a high frequency. Pressing a digit key (such as '1') will generate a sinusoidal tone for each of two fre-
quencies (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 * 0 # D
Note: The phones will not send the DTMF sequence when the call is placed on hold or is held.
Transmitting DTMF Digit
Three methods of transmitting DTMF digits on SIP calls:
l
RFC 2833 -- DTMF digits are transmitted by RTP Events compliant with RFC 2833. You can configure the pay-
load type and sending times of the end RTP Event packet. The RTP Event packet contains 4 bytes. The 4 bytes
are distributed over several fields denoted as Event, End bit, R-bit, Volume, and Duration. If the End bit is set to
1, the packet contains the end of the DTMF event. You can configure the sending times of the end RTP Event
packet.
l
INBAND -- DTMF digits are transmitted in the voice band. It uses the same codec as your voice and is audible to
conversation partners.
l
SIP INFO -- DTMF digits are transmitted by SIP INFO messages. DTMF digits are transmitted by the SIP INFO
messages when the voice stream is established after a successful SIP 200 OK-ACK message sequence. The
SIP INFO message can transmit DTMF digits in three ways: DTMF, DTMF-Relay, and Telephone-Event.
Topic
Transmitting DTMF Digit Configuration
Transmitting DTMF Digit Configuration
The following table lists the parameters you can use to configure the transmitting DTMF digit.
Parameter
account.X.dtmf.type
[1]
<MAC>.cfg
Description
It configures the DTMF type.
Permitted
Values
0-INBAND, DTMF digits are transmitted in the voice band.
1-RFC2833, DTMF digits are transmitted by RTP Events compliant to RFC 2833.
2-SIP INFO, DTMF digits are transmitted by the SIP INFO messages.
3-RFC2833 + SIP INFO, DTMF digits are transmitted by RTP Events compliant to RFC 2833 and the
SIP INFO messages.
Default
1
Web UI
Account > Advanced > DTMF Type
Parameter
account.X.dtmf.dtmf_payload
[1]
<MAC>.cfg

Yealink SIP-T33P Specifications

General

Mounting	Desk/Wall
Handset type	Wired handset
Product type	IP Phone
Product color	Gray
Wall mountable	Yes
Operating system installed	Linux
Lines quantity	4 lines
Phonebook capacity	1000 entries
Number of VoIP accounts	4
Volume control	Buttons
Number of function keys	5
Display diagonal	2.4 \
Display resolution	320 x 240 pixels
Voice codecs	AGC, AJB, CNG, G.711a, G.711u, G.722, G.723.1, G.726, G.729, G.729A, PLC, VAD, iLBC
Security algorithms	AES, HTTPS
Ethernet LAN data rates	10, 100 Mbit/s
Ethernet LAN interface type	Fast Ethernet
RJ-9 ports quantity	1
Ethernet LAN (RJ-45) ports	2
Input frequency	50/60 Hz
AC adapter input voltage	100 - 240 V
Power consumption (typical)	3 W
Power consumption (Power over Ethernet (PoE))	5 W
Number of handles included	1 pc(s)
Operating temperature (T-T)	-10 - 50 °C
Operating relative humidity (H-H)	10 - 95 %

Weight and Dimensions

Depth	186 mm
Width	212 mm
Height	146 mm