15
Interface description
Handset connector The handset is connected via a 4-pin Mini-
Western socket. The audio interface has a
symmetrical design. The audio interface can
be configured by AT commands.
Threeaudio modes are prepared in the GSM
module for this purpose.
Mode 1 (default):
The "Handset for Cellular Engine Siemens
Terminal M20T, MC35T, TC35T, DSB35"
can be connected to the TC35 Terminal
(approved configuration and recommended
handset).
Mode 4:
Any handset can be connected to the
TC35Terminal. The audio parameters can be
adapted by means of AT commands. New
approval must be obtained for this
combination.
Mode 5:
The frequency responses have a linear
setting in this mode for any audio
equipment. Echo suppression and side tone
are switched off.