Abstract: The present invention relates to a measuring device for determining the thickness of a dielectric layer on a conductive substrate. The device comprises a resonance cavity for electromagnetic fields which has a rotationally symmetrical wall, an end plate and an open end and is adapted to be positioned with the open end on the dielectric layer. The device further comprises an antenna which is adapted to excite an electro-magnetic field in the resonance cavity, a reflection measuring unit for determining at least one property of the electromagnetic field and an evaluation circuit for determining the thickness of the dielectric layer from the at least one property of the electromagnetic field. A diameter of the rotationally symmetrical wall varies in a longitudinal direction of the resonance cavity.

Abstract: The present invention relates to a measuring device for determining the thickness of a dielectric layer on a conductive substrate. The device comprises a resonance cavity for electromagnetic fields which has a rotationally symmetrical wall, an end plate and an open end and is adapted to be positioned with the open end on the dielectric layer. The device further comprises an antenna which is adapted to excite an electro-magnetic field in the resonance cavity, a reflection measuring unit for determining at least one property of the electromagnetic field and an evaluation circuit for determining the thickness of the dielectric layer from the at least one property of the electromagnetic field. A diameter of the rotationally symmetrical wall varies in a longitudinal direction of the resonance cavity.

Abstract: The invention relates to a technical embodiment and a method for utilizing air in conjunction with heat pumps and other domestic installations or the house as such, e.g. basements, staircases etc., said air being heated up on photovoltaic systems. The aim of the invention is to devise a technical embodiment with an improved dimensional shape and a method for utilizing air in conjunction with heat pumps and other domestic installations or the house as such, e.g. basements, staircases etc., said air being heated up on photovoltaic systems. The photovoltaic modules comprise modular mounting rails that extend from the gutter to the rooftop and are arranged on the sloped surface/roofing in such a manner that the channels formed in this manner and generating a current or draft of air have lamellar cages on the lower inlet and ventilators on the upper outlet.