Abstract: A device for detecting the malfunctioning of a magnetron which operates at start-up with a high power setting P.sub.0, and which is connected to the terminals (21, 22) of the secondary winding (19) of a high-voltage transformer (8). This device includes a device for measuring (28) the peak voltage value sampled in the supply circuit, a device for storing (29) the voltage value measured at successive instants, a device for comparing (30) two successive voltage values giving, in the event of a difference in value, an excess signal (a-b), and a device for detecting (31) the excess signal suitable for sending a malfunction signal to a counting device in order to determine the frequency of the malfunction.

Abstract: Supply circuit adapted to supply a magnetron (1) and comprising a high loss inductive voltage increasing transformer (8) whose primary winding (13) is mounted in series with a commutation element (14) adapted to chop the voltage and whose secondary winding (19) is connected to the load (1). The circuit comprises also a self inductor (17) mounted in series with the primary winding (13) of the transformer (8), as well as a condenser (18) connected in parallel to the primary winding. The commutation element is a unidirectional current gate (14), and the secondary winding (19) of the transformer (8) is directly connected to the load (1). The circuit is useful, for example, in microwave ovens.

Abstract: Electronic weighing device adapted particularly to be mounted in a personal weighing scale and comprising a capacitative collector (C1) forming a measuring condenser whose capacity varies as a function of the weight to be measured and which has for this purpose a first electrode (10) connected mechanically to a weighing platform (12) and a second electrode (14) mounted fixedly in the casing. The measuring condenser is connected to a measuring circuit, which comprises: a reference condenser (C0) mounted in series with the measuring condenser (C1), each of these condensers having an electrode (14, 16) connected to a terminal (18) common to the two condensers and an electrode (20, 10) connected to an external non-common terminal (22, 24).