Selecting telephone antenna, function - GF82.95-P-3001R

MODELS 230 up to 31.5.04 with CODE (855) TELE AID 

Structogram: antenna selection with TELE AID emergency call 

Fig 1: Selecting Telephone Antenna Flow Chart

A GSM (global system for mobile communication) is required for transmitting a TELE AID emergency call telegram (TELE AID emergency call or telediagnosis), for completing a voice connection or for simply making a phone call.

For normal telephone calls it is the CTEL antenna (A2/22).

If an accident occurs (e.g. rollover) the telephone antenna (A2/22) may be destroyed. There may also be another fault. TELE AID emergency call/telediagnosis is no longer possible then. To ensure that this never occurs, the TELE AID backup antenna (A2/50) is installed in addition to the CTEL antenna (A2/22). This is installed at a location which is largely protected against crash ahead of the roll bar, and is used only if required. For this purpose the telephone transmitter/receiver and TELE AID, D2B (A35/17) has two GMS antenna inputs, via which the corresponding active antenna is switched through to the transmitter/receiver unit of the D2B telephone (A35/13).

The D2B telephone transmitter/receiver unit (A35/13) is integrated in the D2B telephone and TELE AID transmitter/receiver (A35/17). As long as no emergency call is triggered, the CTEL antenna (A2/22) is always active. In the event of an emergency call the CTEL and TELE AID transmitter/receiver, D2B (A35/17) checks the signal level of the CTEL antenna (A2/22). If it is not sufficient, the level of the TELE AID substitute antenna (A2/50) is checked The antenna with the higher signal level is used for connection (see structogram).