Siemens C25 Service Manual page 7

Private Communication Systems
Mobile Phones
In opposite to the MMI board of other phones (e.g. S6 and E10) the ringer (1100) is
not soldered to the board, but is mechanically fixed on one of the shielding covers
(1310) by a metal clip (1190) and electrically connected to the board by a cable and
a plug. The ringer in C25 is of the same type as the one used in C1x mobiles.
C25 does have an external connector of a new type. Since S6 a so called „Molex"-
connector was used, which also offered the possibility to connect an external
antenna to it. The new „Lumberg"-connector which is used in C25 does not feature
such a connection, because the connector for external antenna is located at the back
side of the upper end of the mobile, close to the internal antenna (1130). As a
consequence of this there is no need anymore for a RF cable mounted to the board
nor for a RF plug on it to connect this cable. This improves RF-properties of the
mobile and lowers production costs.
To be able to do measurements on and software update of the telephone, an
adapter cable between Molex- and Lumberg connector will be available. For details
please refer to the chapter Software Programming of this manual.
As already for C1x mobiles, also C25 antenna (1130) is of a plug-in type inserted into
the lower case shell (1030), which also carries the microphone (1110). Make sure
that the microphone contact springs are not dirty or damaged during repair process.
Attention:
Because the C25 is a dual-band mobile operating on GSM900 and GSM1800, the
antenna is different from the one used in C10 and C11. Please refer to the spare
part list for ordering the right type of antenna!
The keypad (1150) and the loudspeaker (1120) with it's retaining clip (1125) are
mounted into the upper case shell (1020).
The dust protection frame and the display window are included in the display module
(1170).
Attention:
The displays (1170) of C25 and C2588 are different as well as their RF-and control
modules (1010) and the mobile software. Please refer to the spare part list for
ordering the appropriate components!
V 1.0
Service Manual C25 / C2588 ICP CD ST
R. Fleuren
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