MARKER FOR RESONANT DETECTION SYSTEM Russian patent published in 1999 - IPC

FIELD: alarm equipment, in particular, for burglars detection. SUBSTANCE: device has substrate, which is made from electric- insulation material, and resonant circuit which is located on it. Resonant circuit has inductance coil which is provided by track of specific shape, and capacitance element, which is provided by at least two electrodes which are spaced by substrate and are designed as current-conducting electrode regions. Ends of track are connected to respectively to both electrodes. In addition device has at least one current-conducting insulated region, which is located on substrate in same plane as one electrode. Edges of said region and of this electrode are located in opposite and are spaced by distance which depends on discharge gap. Second claim of invention discloses device design in which insulated region is located in plane of conducting track, is connected to its end, while discharge gap is located between their edges. EFFECT: increased precision of setting of characteristic frequencies, increased precision of detection. 9 cl, 4 dwg