Abstract: A plurality of posts and actuator posts connected to a foundation and to a torque tube on which solar panels are duly mounted is disclosed. The actuator posts include a hinge next to a radial arm that is disposed solidly connected to the torque tube, the arm being hinged at the other end to a linear actuator with screw drive, the bottom end is connected to the actuator post by a joint. Each linear actuator is actuated by a gear that engages with an endless screw solidly connected to a Cardan-type drive shared by all the actuators and is actuated by an electric motor, the Cardan-type drive fitting closely to the torque tube by supports.

Abstract: In a switch-mode power supply, a transformer is used to transmit power during the forward-sweep time. The transformer is also used to transmit a control or regulating variable during the flyback time.

Abstract: A switching power supply in which a regulating voltage generated on the secondary side of the circuit is transferred to a control circuit on the primary side of the circuit so as to stabilize the dc operating voltages produced on the secondary side. In order to avoid the dangers involved from the absence of such regulation, a further or emergency regulating voltage is generated on the primary side of the circuit and if the regulating voltage from the secondary side is absent, the system is automatically switched to the further regulating voltage generated on the primary side, which further regulating voltage regulates the operating voltages to at most the rated values and preferably to values that are reduced by up to 10%.

Abstract: A short-circuit protected mains supply unit, especially for the screen-text component of a television receiver. A conventionally controlled unit is expanded in accordance with the invention with only a few components (T1 and T2) in such a way that it can be turned on electronically and its output is protected against short circuits.