Audi Entry MIB, Обучение по обслуживанию

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15
618_041 Display of radio menu during FM reception
Reference
Information on the various RDS services can be found on page 34 of Self-study Programme 435 – Audi 3rd Generation MMI.
The analogue radio receiver unit for the Modular Infotainment System is always integrated in the electronic information systems control
unit 1 J794. Depending on the equipment options fitted, the J794 may also include a DAB radio tuner.
The radio tuners support most of the
RDS* services generally available today. Which particular RDS services are actually available in each
case depends on the station being received at the time in question.
The basic designs of the radio tuners for the Standard and High-spec MIB versions are explained below.
Analogue tuner reception concept
Standard MIB
The analogue radio receiver (tuner) for the Standard MIB has a two separate receivers in total.
Tuner 1 is an AM/FM tuner (see schematic diagrams on pages 16 and 17).
AM reception is provided exclusively by Tuner 1.
Tuner 2 is an additional FM tuner.
Radio tuner
If FM reception is poor, the selected station is received simultane-
ously by Tuner 1 and Tuner 2. The two signals are then merged to
form a combined signal.
If the signal received by one of the tuners is good enough to ensure
interference-free reception and playback through the speakers is
possible, the other tuner is used for the station search function.
The best aerial-tuner path is always used for audio output (role
swapping).
Because a station search is carried out at regular intervals, the
main screen of the FM radio menu is constantly updated with the
FM radio stations currently receivable. The station list is thus kept
up to date and unavailable stations removed from the list.
Furthermore, the AM station list is also updated in FM mode if the
reception conditions allow – in which case Tuner 2 provides the FM
audio signal and Tuner 1 performs the AM station search.
If a navigation system is fitted, a third FM tuner (Tuner 3) is fitted
for receiving
TMC* data. That tuner continues to be used for
monitoring traffic bulletins if the audio tuner is not tuned to a TP
station. It is also used for the station search function if the recep-
tion conditions require the use of aerial diversity.
The separate station memory can be used to create a personalised
station list. It can store up to 50 stations from any reception area
and lists them in the user-defined order.
The radio supports the Radiotext and Radiotext Plus data services.
This enables programme-related information to be displayed if
broadcast by the station concerned (e.g. artist, title, current
programme).