Radio mode, function

Navigation processor with

GPS receiver and

gyrosensor

CC player

Central

computer

Audio signal

processing

CD drive

Diagnosis

Radio tuner

Radio and navigation module

(A2/56)

Sound amplifier

(A2/13)

Amplifier
FM/AM
(A2/18)

Activation

Data link connector (X11/4)

FM/AM

signals

Antenna
Rear window
(A2/32)

FM

AM

AF signals

Vehicle loudspeakers

D2B

Antenna splitter

Radio

(A2/5)

AM

AM

FM

Microphone

(B25/6)

MCS radio system block diagram illustrated with antenna system and following equipment:

 Sound system (code 810)

B25/6 Sound amplifier microphone

The components marked are significant for the Radio mode

Abbreviations

AM Amplitude-modulated

FM Frequency-modulated

AF Audio frequency (20Hz...20kHz)

D2B Digital data bus

The MCS radio menu is activated by pressing the "RADIO" button on the radio and navigation module (A2/56).

Radio reception, function

The rear window antenna (A2/32) receives the high frequency FM and AM signals.The music, voice and/or data signal is superimposed on these high-frequency carriers. The radio antenna splitter (A2/5) decouples the AM signals from the heater current in the rear window and relays them to the FM/AM amplifier (A2/18), while the FMsignals are transmitted directly from the rear window to the FM/AM amplifier (A2/18). The FM/AM amplifier (A2/18) filters the frequencies of the

radio frequency bands from the high frequency signals received and amplifies these signals.

The amplified signals are then transmitted to the radio tuner integrated into the radio and navigation module (A2/56) by the FM/AM amplifier (A2/18) via a common co-axial line (FM, AM)

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The radio receiver demodulates the high-frequency signals, i.e. 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 loudspeakers.

The MCS radio system offers the following possibilities for station selection and adjustment:

 manual station search is activated by actuating the "joystick" to left or right. The station search feature stops at the next station found, even when the "joystick" continues to be actuated.

 Automatic station search with scan function can

be activated by

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pressing the multifunction "Scan" key. Each station received in the frequency range is played for approx. 8 sThis function is possible only in the forward direction. When activated "Scan" appears inverted on the display.

 Manual fine coordination
The frequency can be changed when the "joystick" is moved up or down.

 Station selection from memory
For each frequency range (FM, AM) there are 10 memory buttons available. Press button of number block approx. 2 s to store a station.When a station is stored it is confirmed by an acoustic signal.Any station stored previously is written over.

 In the frequency range WB (weather forecast) 7 stations are preset. These stations can be called by momentarily pressing the desired number of the number block.

 Station selection with frequency input via number block
Pressing the "*" button followed by actuation of the number keys allows direct entry of the desired frequency. Undesired entries can be erased with the "Clear" button.

 Station selection from the FM or AM station list
by pressing the multifunction key "List" all stored stations in the momentary frequency range are listed. Exit station list by pressingFM or AM multifunction key.

 Automatic storage
The "Auto" multifunction key (when pressed for longer than 2 s) starts automatic storage of the 10 strongest stations in the corresponding frequency range.The stations are stored according to the strength of the received signals in decreasing order.