Abstract: When a light-emitting diode is controlled for transmitting high-frequency signals, such as video signals, or quick-changing analog signals, the electro-optical signal conversion is subjected to distortions due to temperature variations in the barrier layer of the diode which arise due to rapidly varying power losses. The circuit presented herein includes a compensating stage operatively connected to the diode, for alleviating such signal distortions. The system is capable of differentiating between the respective conditions of rising and falling edges of the control in the representative signal of signals to be transmitted.

Abstract: A protective screen or grating, especially a protective screen or grating for drift or blown sand or the like, for an electrical air-cooled machine, comprising essentially vertically arranged profile ledge members disposed in at least two rows, the profile ledge members being provided with at least one row of guide devices located downstream with respect to the flow direction of the cooling air and forming channel walls.

Abstract: A method for starting a blower in the form of a single-stage radial fan installed in a pressure system such as the circulating cooling system of a turbogenerator in which the resistance of the pressure system is varying during the starting operation by means of a starting duct provided with a throttling element. The throttling element is closed at any desired blower speed ranging from 10 to 100% of its rated speed when the point of intersection between the pressure system characteristic, modified on the basis of the open throttling element, and the blower characteristic has been reached whereupon the desired point of operation conforming to the blower characteristic and the system characteristic will regulate itself automatically.