The paintbrush-cleaning device includes a housing with an open top, a bottom drain and a central space, containing paintbrush-cleaning liquid therein. Each of the segments is encoded as a symbol for transmission over a communication channel. The first-side waveguide is positioned for incidence of a wavelength-multiplexed optical signal into the lens. The OPC server responds to the request using a second transmission channel. The existing transponder in the aircraft can be removed thereby leaving an opening in the aircraft and the transponder installed in the opening. A plurality of extending material, such as disposable cloth or shop towels, is inserted in the empty space in between the projection members, such that both ends of each extending material extends radially from the central body.