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GF82.60-P-2001T Radio Mode, Function



GF82.60-P-2001T Radio Mode, Function
- with CODE (525) MB Audio 50 APS radio






Radio reception, function
The antennas in the rear window receive FM and AM (LW, SW) radio frequency signals. The music, voice and/or data signal is modulated upon these high-frequency signals. The left antenna amplifier module (A2/64) 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 left antenna amplifier module (A2/64) via a joint coaxial line (FM, AM) to the radio receiver in the audio gateway control unit (N93/1). The radio receiver demodulates the high frequency signals, in other words it separates the useful information (audible frequencies) from the carrier signal (inaudible). The demodulated audio signals are amplified and converted into sound signals by the vehicle speakers.

The radio menu is accessed by pressing the"FM" or "AM" key.

Different ways of tuning in stations:
^ Tuning by list of stations
^ Tuning by program type list
^ Tuning by frequency list
^ Tuning by station search
^ Tuning by station search on multifunction steering wheel
^ Tuning by autostore memory
^ Tuning by scan search (the stations of a waveband are played for 8 seconds)
^ Manual tuning
^ Tuning by station memory (10 stations preset for each waveband and 7 stations in the weather band)
^ Tuning by manual frequency input (via the 12-key panel of the radio control panel and navigation unit (A2/56))

Furthermore, the following functions are available. They are shown on the display of the radio control panel and navigation unit (A2/56):
^ AM noise suppression
^ Selection of RDS stations with good reception
^ RDS functions PS, TP, TA, EON, PTY, PTY 30/31
^ FM antenna diversity, function
^ TMC (only in combination with navigation)

Radio Data System (RDS), function (regional mode)
Apart from the normal radio program, many radio stations (FM) transmit additional inaudible digital information such as station names, program type (PTY) (e.g. pop, culture, etc.) and traffic radio recognition. This information is evaluated by the radio control panel and navigation unit (A2/56) and displayed on the screen, provided that:
^ An RDS station is tuned
^ The RDS function is activated

FM antenna diversity
If problems in the reception occur while driving, the radio control panel and navigation unit (A2/56) tries to receive the selected station on an alternative frequency with the aid of the second receiver and to switch over accordingly in the event of an improvement in reception.

At certain times, some radio channel programs are subdivided into regional programs. As the radio unit, as described above, attempts to automatically switch to an alternative statio frequency because of problems with the reception, this may also lead to a change in the regional program. If this is not desired, the "Regional program" entry can be activated under the "FM settings" menu.

FM antenna diversity, function
The antenna diversity function switches between the FM antennas in the rear window depending on the reception. The function proceeds automatically and is carried out by the left antenna amplifier module (A2/64). The radio tuner merely generates the ZF signal (intermediate frequency), which is used by the antenna amplifier as a reference for changing the FM antenna.

RDS diversity/two-receiver technology, function
The system consists of two FM receivers, an audio receiver and a search receiver.

After activating the radio system on the radio control panel and navigation unit (A2/56), the search receiver automatically generates a list of FM stations received which is continually updated during operation. Data such as reception quality, programs and alternative frequencies are stored. The audio receiver can therefore switch over inaudibly to an alternative frequency. The list appears in alphabetical order when the "FM station list" is called up. The displayed stations can be activated through selection and confirmation.

The station list is only available when the RDS function is activated.