MIX Modem - GSM
User Manual V.1.1
Pag. 16
Subject to change without prior notice
The electrical characteristics of the voiceband part vary with the audio mode. Specifications are listed
in following table. To suit several types of audio equipment, three audio modes given by default can be
selected by the AT command AT^SNFS.
The audio mode 1 are optimized for the reference handset (type Votronic) connected to the MTX-
63I/65I Terminal, and to ensure that the reference parameters are always within the limits demanded
by the standards they cannot be changed by AT command. Furthermore, the reference parameters are
set as factory default.
In audio mode 4 and 5, the gain in the microphone, earpiece and the side tone path can be adjusted
from the cellular device application by using further AT commands.
Please note that the 2nd audio interface of the MODEM TC/65I module is not connected in the MTX-
63I/65I Terminal. Audio modes 2, 3 and 6 can be selected by setting AT^SAIC=2,1,1,
Mode No AT^SNFS=
1 (Default settings,
not adjustable)
4
5
Name
Default Handset
User Handset
Plain Codec 1
Purpose
Recommended
handset
User
provided
handset
Direct
access
to
speech coder
Gains programmable via AT command
NO
YES
YES
Sidetone
YES
YES
YES
Volume control
NO
YES
YES
Echo control (send)
Cancellation
and
suppression
Cancellation
and
suppression
NO
Noise suppression
YES
YES
NO
MIC input signal for 0dBm0 @ 1024 Hz
(at default gain settings)
12.5 mV
12.5 mV
400 mV
Earpiece output signal in mV eff. @
0dBm0, 1024 Hz, no load (at default gain
settings); @ 3.14 dBm0
475 mV
475 mV (default @
max volume)
1.5 V 6.0 Vpp
Sidetone gain (at default settings)
24.9 dB
24.9 dB
-∞ dB
