An impact-resistant modified, flame-resistant and mineral-reinforced polycarbonate composition is disclosed. A first switching circuit is provided in order to select a pair of analog voltages generated across one of resistors in a first resistor string. The shunt includes a pair of electrical contacts and the shunt has a first position in which the electrical contacts are in electrical communication with the circuit and a second position in which the electrical contacts are removed from electrical communication with the circuit. The radiating layer also comprises a conductive coating disposed on the inner perimeter sidewall or the outer perimeter sidewall and a feed line disposed on a second side of the dielectric substrate.