GF82.60-P-2001P Radio Mode, Function
GF82.60-P-2001P Radio Mode, Function
- with CODE (352a) COMAND operating and display system
Radio mode, function
After the COMAND operating, display and control unit (A40/3) has been activated by pressing the "FM/AM" button, the antennas in the rear window receive high-frequency signals for ultra-short wave (FM), medium wave (MW) and long wave (LW). With Mode 209, the MW and LW high-frequency signals are received by the AM rear window antenna amplifier (A2/16). The music, voice and/ or data signals are modulated upon these high-frequency signals. The window antenna amplifier module 1 (A2/71) (left antenna amplifier module (A2/64) for Model 209.4) filters the frequencies of the radio frequency bands out of the high-frequency signals received and amplifies them. The amplified signals are then transmitted from the window antenna amplifier module 1 (A2/71) (Models 203, 209.3) or left antenna amplifier module (A2/64) (Model 209.4) to the radio receiver via a common coaxial cable.
The radio receiver is integrated into the COMAND operating, display and control unit (A40/3) and separates the useful information (audible frequencies) from the carrier signal (inaudible). The demodulated audio signals are amplified and converted to sound signals by the vehicle speakers.
FM antenna diversity, function
The antenna diversity function switches between the FM antennas in the rear window depending on the reception. The function runs automatically and is executed by the window antenna amplifier module 1 (A2/71) (Models 203, 209.3) or left antenna amplifier module (A2/64) (Model 209.4). The radio tuner of the COMAND operating, display and control unit (A40/3) only generates the IF signal (intermediate frequency), which serves the antenna amplifier as a reference for changing the FM antenna.
2-receiver technology function
After the COMAND operating, display and control unit (A40/3) has been switched on, a 2nd (integral) radio receiver automatically generates a list of the FM-stations received, this list being continuously updated during operation. This list appears, sorted alphabetically, when the "FM station list" menu is called up. The stations which are displayed can be activated by selecting and confirming.
The station list is only available when the Radio Data System (RDS) function is active. If reception interference occurs while driving, the COMAND operating, display and control unit (A40/3) tries to receive the selected station on an alternative frequency with the aid of the 2nd receiver and then tries to switch over accordingly if reception is improved.
At certain times, some radio channel programs are subdivided into regional programs. As the COMAND operating, display and control unit (A40/3) automatically switches to an alternative station frequency in case of reception interference, this may also lead to a the reception of a different regional station.
RDS function
Apart from the normal radio program, many radio stations (on FM) transmit additional digital information such as station names, program type (PTY) (e.g. pop, culture, etc.) and traffic radio recognition. This information is evaluated by the COMAND operating, display and control unit (A40/3) and indicated on the display if:
^ An RDS station is tuned
^ The "RDS" function is activated
The radio component of the COMAND operating, display and control unit (A40/3) also provides:
^ a station list of the currently most powerful FM stations in RDS mode
^ an automatic memory for the most powerful MW/LW stations
^ a program type selection (PTY, e.g. culture, entertainment, pop) for FM-stations in RDS-mode
Station selection options:
^ Automatic station search with scan function (the stations in the frequency range are each played for 8 s)
^ station search at the multifunction steering wheel (MFL)
^ Manual station search
^ Station selection with station list
^ Station selection with number buttons
^ Station selection by entering the frequency (e.g. 92.2 MHz)
^ station selection from the memory (10 stations per waveband)
