FAKRA plug
FAKRA, Facharbeitskreis Automobil, is a group of experts from German automotive manufacturers and suppliers. With the FAKRA connector, this working group has defined a connector interface that can be used for communication inside the vehicle and with equipment outside the vehicle.
The FAKRA connector, which is defined under DIN 72594-1 and ISO 20860-1, is based on the SMB connector. However, it can be coded for different signals. In total, there are more than ten differently coded connector types, which are color-coded and cannot be interchanged due to guide notches. The plug is equipped with a snap lock and has a sturdy plastic protection. The coaxial connector is designed for a cable impedance of 50 Ohm and a frequency range up to 6 GHz. The insertion loss is only 0.1 dB at 4 GHz and the return loss is >18 dB. The contact resistance of the inner conductor and shield is 5 milli-ohms. The maximum current is 1 A DC.
As for the connector codings, they are color-coded and designed for different signal types and applications. They have guide notches and can only be used for a specific signal type. FAKRA connectors with black coding are antenna connectors for AM and FM broadcasting. They carry the designation "A". The "C" coded connector is blue and for the GPS system. The D-coded plug is bordeaux and for mobile radio signals of the GSM network. The E-coded plug is green and for television. And so on.
FAKRA plugs are available in round and rectangular versions as a single plug (single), as a double plug 8 mm for a round and a square plug and in a 12.7 mm version. There is also a quad version for four round FAKRA connectors.