TV-mode, function - GF82.85-P-2011TA

MODEL 211.0/2 up to 31.5.05 with CODE (527) COMAND APS (with navigation) with CODE (860) TV tuner

MODEL 211.0/2 as of 1.6.05 up to 31.5.06 with CODE (527) COMAND APS (with navigation) with CODE (863) Digital/analog TV tuner

Fig 1: Networking Of TV-Mode Components

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

COMAND operating, display and control unit (A40/3) with code (813) Voice control system (VCS)

Shown on MODEL 211.0

Function requirements:

On-board power supply
Authentication positive
Circuit 15R ON

TV system control

The COMAND TV system is controlled via the COMAND operating, display and control unit (A40/3). Communication between the COMAND operating, display and control unit (A40/3) and the TV tuner (A2/10) (with code (860) TV tuner) or TV combination tuner (analog/digital) (A90/1) (with code (863) Digital/analog TV tuner) takes place over the Media Oriented System Transport (MOST).

The COMAND TV system has the following features:

4-fold antenna diversity
Multistandard capability, i.e. Color decoder for NTSC, PAL and SECAM standard with automatic detection
SCAN function (stations are played successively)
Videotext decoder
10 storage spaces for the station list sorted by reception field strength and 10 further storage spaces for stations which can be chosen at will
OSD (On-Screen-Display) function for displaying text on the color liquid crystal display (LCD)

The TV tuner (A2/10) or TV combination tuner (analog/digital) (A90/1) is located behind the left inner wheelhouse liner above the navigation processor (N41/1).

TV reception

The 4 TV antennas in the rear window receive the TV high-frequency (HF) signals independently from each other. The video signal and sound signal are modulated on these high frequency (HF) signals. The right antenna amplifier module (A2/65) and amplifier module 2, window antenna (A2/72) filter the frequencies of the TV frequency bands out of the received HF signals and amplify them.

The amplified signals are sent over 4 separate coaxial lines to the TV tuner (A2/10) or TV combination tuner (analog/digital) (A90/1). The TV tuner (A2/10) or TV combination tuner (analog/digital) (A90/1) chooses the strongest of the incoming antenna signals (antenna diversity), selects the desired station and then demodulates the TV audio and TV video signal in accordance with the given transmission standard (e.g. PAL). The video and audio signals thus processed are sent as red-green-blue synchronous (RGBS) video signals and as low frequency (LF) audio signals (TV audio) to the COMAND operating, display and control unit (A40/3) and the rear display (A40/7) (with code (861) TV rear screen).

Analog TV reception, function

In the same way, the TV tuner (A2/10) receives and processes terrestrial television programs which are broadcast in all standards. It supports all channel lists and audio standards. The audio quality is limited to MONO.

Digital TV reception, function

The TV combination tuner (analog/digital) (A90/1) uses an integrated DVB-T receiver to not only receive analog television stations but also terrestrial digital television stations over the antenna structures installed. The switchover from analog to digital television reception is performed automatically depending on the current reception status. A digital television station is denoted by a "+" added to the station name. The audio quality of the audio signals output via the vehicle speakers is stereo.

TV picture display

The TV picture is forwarded over a direct video line to the COMAND operating, display and control unit (A40/3) and then only shown on the display when the parking brake is engaged and the selector lever set to P or N position (both pieces of information are sent via the Controller Area Network bus class B (interior) (CAN-B). From a vehicle speed of > 5 km/h, only playback of the audio signals is possible.

In contrast to this, the video signals are shown on the rear display (A40/7) even while the vehicle is in motion. The TV system can then also be operated in the rear of the vehicle using the remote control (with code (816) Remote control for radio).

TV sound replay

The TV tuner (A2/10) or TV combination tuner (analog/digital) (A90/1) routes the TV audio signal over separate lines to the audio gateway control unit (N93/1). There, the signals are amplified and converted into acoustic signals by the vehicle loudspeakers.

2 headphones can be connected to the rear display (A40/7). The TV sound can always be heard on the headphones, regardless of the audio source that is being played on the vehicle speakers.

TV tuner, location/task/design/function	up to 31.5.05 With code (860) TV tuner	GF82.60-P-3109TA
TV tuner, location/task/design/function	1.6.05 With code (863) Digital/analog TV tuner	GF82.60-P-3109TB
Antenna amplifier module, location/task/design/function	except CODE (494), USA version except CODE (498) Japanese version	GF82.62-P-3105T
Amplifier module for window antenna, location/task	Model 211.2 except CODE (494), USA version except CODE (498) Japanese version	GF82.62-P-3114T