An improved directional coupler is distinguished by the following features: an attenuation circuit (27) is adjacent and is connected to each of the two coupling line ends (25) on the coupler substrate (19null), or an attenuation circuit (27) is connected to one coupling line end (25) with a terminating resistor (49) being connected to the other coupling line end (25) on the coupler substrate (19null), electrical level evaluation (33) is provided on the coupler substrate (19null), and an interface device (35) for connection of possibly unshielded cables (41) is provided on the coupler substrate (19null), or possibly unshielded cables (41) are connected to the level evaluation circuit device or are connected downstream from this on the coupler substrate (19null), via which the RF signals which are obtained via the coupling line piece (23) can be passed on in the form of analog signals.