Antenna: Description and Operation

Antenna System (4D):

Aerial System

Aerials
The aerials for radio reception are integrated into the rear window and are located as follows:
- The AM aerial is placed at the top of the rear window.
- The FM aerial(s) is/are integrated into the heating element.

The rear window is the same for all markets. The aerial signal is amplified in an amplifier placed in the right C-pillar. The aerial amplifier is available in two versions, depending on the market: black and red.

The aerial amplifier is supplied with trigger voltage from pin 7 of the main unit and grounded by being bolted to the chassis.

For retrofit radios, the black variant is used for all markets.

In the left C-pillar is an aerial filter which grounds the electric heating element but blocks the aerial signal from ground. The aerial filter is fitted as standard to all cars.






Aerial System 1, Black Version

1 AM aerial in a separate loop at the top of the rear window.
2 FM 1 aerial coupled with the electric heating element.
To prevent the aerial signal being emitted when power is supplied to the electric heating element, a filter is fitted in the aerial amplifier which blocks the aerial signal. On the ground side of the heating element is an aerial filter which blocks the aerial signal from ground.
3 The electrically heated rear window is connected to the aerial amplifier and filter. A capacitor prevents the current from reaching the aerial amplifier. The electrically heated rear window is grounded through the aerial filter.

The amplified aerial signal is supplied to the radio via coaxial cable.






Aerial System 2, Red Version

1 AM aerial in a separate loop at the top of the rear window.
2 FM 1 aerial connected with the electric heating element.
To prevent the aerial signal being emitted when power is supplied to the electric heating element a filter is fitted in the aerial amplifier which blocks the aerial signal. On the ground side of the heating element is an aerial filter which blocks the aerial signal from ground.
3 FM 2 aerial connected to the same connector as the AM aerial on the rear window. This is connected to a loop across the AM aerial and to the electric heating element.
4 The electrically heated rear window is connected to the aerial amplifier and filter. A capacitor prevents the current from reaching the aerial amplifier. The electrically heated rear window is grounded through the aerial filter.

The aerial amplifier contains a switching function which selects the best FM signal in cooperation with the radio (selects FM 1 or FM 2).

The amplified aerial signal is supplied to the radio via coaxial cable.