rely on the transmission and receipt of electromagnetic waves e g motorcycle to motorcycle communication devices the antenna 20 may be connected to the device 24 at a remote location on the vehicle by way of a coaxial cable 26 it should be noted that other suitable cable types may likewise be utilized in this particular embodiment the decoupling circuit 22 comprises an input filter 28 to prevent electrical noise associated with the upstream brake light switch 14 from interfering with the electromagnetic waves received by the antenna element 17 within the antenna 20 the high impedance circuit 30 serves to electrically isolate the antenna 20 from the filter 28 the brake light switch 14 and the associated wiring 16 within the vehicle as can be appreciated the entire assembly forming the apparatus 10 may be provided as a single cable with appropriate leads for connecting the brake light to the switch 14 and device 24 e g radio respectively in the illustrated example the high impedance circuit 30 comprises a common mode choke 32 a providing a high impedance for isolating the wiring serving as the antenna element 17 within the am broadcast band the common mode choke 32 a may be associated with optional capacitors 32 b 32 c these capacitors 32 b 32 c may be omitted if the antenna 20 functions.