Systems and methods for communication of scaleable-coded audiovisual signals over multiple TCPIP connections are provided. The external sheet is inward bent in the visible areas of the door or attached part, the sheet edges being practically parallel to the plane of attached parts in the invisible areas of the door or attached part. Releasing of the fuel from inside the spare tank is activated by power on the switch connected to a solenoid valve blocking the spare fuel suction pipe. The correlation of un-averaged signal strengths can be used to determine which beams have the same polarisation.