This versatile instrument indicator is a godsend, because it combines with its simplicity of use two indicators. The device allows to detect hidden wiring, but to detect any metal object located in the wall or floor (rebar, old wires, etc.), and, thus, significantly will facilitate the search space for the equipment cache.
The device consists of two independent devices: the metal detector and indicator hidden wiring (Fig. 1). Transistor VT1 is assembled RF generator, which is introduced in the mode of excitation voltage adjustment on the basis VT1 via potentiometer R6. RF voltage is rectified by the diode VD1 and translates the comparator assembled at the shelter DA1, in the position in which HL1 led goes out and the generator of a periodic sound signals collected on the chip DA1 is turned off condition. By rotating the sensitivity control R6 set mode on the VT1 threshold, which is controlled by turning off LEDs HL1 and the periodic signal generator. When enters the field of the inductance L1/L2 of a metal object the generation fails, the comparator switches and the position at which led lights up HL1 and piezoceramic emitter served periodic voltage has a frequency of about 1000 Hz with a period about 0.2 C.
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