An apparatus and method is provided for disabling radio frequency signal transmissions from a wireless communications network modem when in proximity to sites where explosive devices are being detonated. The device comprises a clamshell base having first and second trays latchable in a closed condition and pivotable to an open condition. A main control unit and a drawing unit of the apparatus cooperatively serve as a controller of the apparatus by changing gradation ratio of the first and second pixel areas so that the gradation ratio of the second pixel area becomes greater than the gradation ratio of the first pixel area according to the input of the adjustment value. The first object system may be at least one of a managed object system and an unmanaged object system, and the second object system may be at least one of a managed object system and an unmanaged object system.