the power grid pins pass through 2 cardboard sheets 603 so that the spring loaded power pins can make contact with the center power grid layer the right diagonal sensor pins pass through holes drilled into the last cardboard sheet 602 to allow the spring loaded pins to make contact with the right diagonal sensors fig7 show a wire frame drawing of the front of the target as you can see the spacing is designed so that they all converge at each intersection this allows for very accurate sensing if a bullet strikes between multiple sensors on the same layer because both sensors will fire and the gap exact location is known for example an exact location of impact can be determined if a bullet were to pass through the gap at the intersection of all 4 conductive layers if you think about it a target of this type with foil laminated on both sides of an insulator should produce a capacitor therefore with a bullet disturbing the capacitance a circuit could be designed to capitalize on that fact fig8 shows a capacitive coupled simulation of the same target using the change in capacitance as the when the bullet shorts out 2 of the plates by passing either commercial capacitors across each of the columns in a daisy chain fashion or by placing a foil strip that is shorted to all of the sensors such that it would product a different capacitance determined by the distance of the single sense wire on each set of sensors for example if a foil strip.