Abstract: Detector comprising two windings (1,2) disposed in two ferrite half-pots (3,4) opposite to two non-ferromagnetic metallic elements (5,6) one at least of which is movable. A pulse generator (9) feeds the two windings through resistances (7,8) coupled to a reference potential.Two circuits (10,11) detect the peak values of the resultant signals at the common points between the windings and their charging resistance. An operational amplifier (12) creates the difference of these peak values. A diode (13) permits the discharge of the windings through the resistances (7,8).Application to detectors of differential pressure, and to devices for the measurement of displacements.

Abstract: A thermostatically and hygrostatically controlled cabinet for storing foodstuffs has a food storage chamber partially surrounded by an elongated space communicating with the food storage chamber through a grid. A fan establishes forced air circulation inside the elongated space, through the grid and inside the food storage chamber. An evaporator and a provision of water are located inside the elongated space and a compressor and a condenser are positioned outside the elongated space and the storage chamber. Thermostatic control means start the compressor when the temperature inside the food storage chamber exceeds a rated value and, after a time delay, also start the fan.