Sun sensor for brightness-dependent control of DuoFern devices This brightness sensor from the Rademacher DuoFern product line enables automatic control of DuoFern actuators and the devices operated via them, such as awnings or roller shutters. The sensor is attached to the inside of window or door panes with the suction cup on the back. Thanks to battery and radio operation, there is no need for wiring. Communication with DuoFern actuators takes place via radio. The sensor detects the intensity of daylight and automatically triggers the desired action when a specified threshold value is reached, such as raising the roller shutter in the morning or extending the awning in strong sunlight. In addition, the sun sensor also enables manual control of the coupled devices thanks to its operating buttons. As a practical additional function, a vibration sensor is also installed; this detects a glass breakage, for example. Thus, with the appropriate setting via app and e.g. coupling with a sire