The sending module is for transmission of 4 switching informations and suits a current-value. The module sends the information,as long as at least one digital input is active. In case of the right acknowledgement of the receiver,the message is 3x/s repeated. The deactivation of digital input originated the message of a out-signal to the receiver, which switches-off the corresponding out-put. If no acknowledgement comes, sending continues for 3 seconds, in order to contact the eventually clocked receiver. For plug-in of LEDs, Piezodisk etc. are available for further input and outputs. Selectable frequencies (433.62 and 434.22 MHz) together with a special transmission protocol lead to an extremely trouble-free control Coverage possible up to 1000m depending on places.