GF82.85-P-2030TME Audio Mode, Function

GF82.85-P-2030TME Audio Mode, Function
- with CODE (525) MB Audio 50 APS radio
- Radio, CD


Radio mode, function
After switching on the radio control panel and navigation unit (A2/56), the antennas in the rear window receive high frequency (RF [HF]) signals for ultra-short wave (FM), short wave (SW), medium wave (MW) and long wave (LW). Modulated onto these RF [HF] signals are the music, voice or data signals. The left antenna amplifier module (A2/64) filters the radio frequency band frequencies from the received RF [HF] signals and amplifies them. The amplified signals are then transmitted by the left antenna amplifier module via a coaxial line to the 2 radio tuners in the audio gateway control unit (N93/1).
The 2 radio tuners separate the useful information (audible frequencies) from the carrier signal (not audible). The demodulated audio signals are amplified and converted into sound signals by the vehicle speakers.

Antenna diversity, function
In the case of the "antenna diversity" function, reception-dependent switching over is carried out between the FM antennas of the rear window. The function runs automatically and is carried out by the left antenna amplifier module. The 2 radio tuners in the audio gateway control unit merely generate the intermediate frequency (IF [ZF]) signal which serves as a reference for changing the FM antenna.

2-receiver technology function
The 2nd (integrated) radio receiver in the audio gateway control unit automatically generates, after the radio control panel and navigation unit is switched on, a list of the FM stations received which is constantly updated during operation. This list appears, sorted alphabetically, when the "FM station list" menu is called up.

The displayed stations can be activated through selection and confirmation. The FM station list is only available, if the "Radio data system (RDS)" function is activated. If reception faults occur while driving, the radio control panel and navigation unit tries to receive the selected station on an alternative frequency with the aid of the 2nd radio receiver and to switch over accordingly if reception improves.

Certain programs of the various radio broadcasting companies are subdivided into regional programs at certain broadcasting times. As the radio control panel and navigation unit automatically switches to an alternative frequency of the station in case reception problems, this may also lead to the reception of a different regional program.

RDS function
In addition to the radio program, many radio stations (FM [UKW]) additionally broadcast non-audible digital information.
Possible information is for instance the station name or alternate frequencies, on which the same program is broadcast. This information is evaluated by the radio control panel and navigation unit and shown on the display, if the following prerequisites are met:
^ An RDS station is tuned in.
^ The "RDS" function is activated

The 2 radio tuners in the audio gateway control unit also offer:
^ a station list of the currently most powerful FM stations in RDS mode
^ An automatic memory for the strongest AM stations
^ a selection by program type (e.g. pop, culture) for FM stations in RDS mode

Station selection options are:
^ automatic station search with scan function (the stations of one waveband are played for 8 s)
^ Station search on multifunction steering wheel (MFL)
^ Manual station search
^ Station selection using list of stations
^ Station selection using numeric keyboard
^ Station selection using frequency input
^ station selection from the memory (10 stations per waveband)

CD mode function
The radio control panel and navigation unit also features an integrated CD drive which is used to play back audio CDs. It is also possible to play audio data in MP3 format.

As well as playing back audio signals, the radio control panel and navigation unit provides the following functions in CD mode:
^ "Random" function
All the tracks of a CD are played according to the random principle.
^ "Repeat" function
Either a track or a CD is repeated.
^ "Scan" function
Each track of a CD is played briefly for 8 s. After this has been run through completely, the scan function is automatically terminated.
^ "Select next/previous" function
The system only jumps forward or backward to the next or previous track; no audio signals can be heard in the process.
^ "Music search" function
The music that is being played is audible during music search. This enables certain sections of a track to be played or skipped.
^ "Track list" function
The desired track is selected and confirmed on the display of the radio control panel and navigation unit.

In addition to the listed functions, supplemental information is shown on the display of the radio control panel and navigation unit (e.g. playing time, track list and name of the performer).