A method and apparatus for sensing radio frequency signals. A radio frequency strength sensing apparatus converts a sensed radio frequency signal to an audible tone. The apparatus comprises a radio frequency detector, a voltage to frequency converter, and a speaker system. The radio frequency detector is capable of detecting radio frequency signals over a selected frequency range with different signal strengths and capable of outputting a logarithmic voltage that varies with signal amplitude change. The voltage-to-frequency converter is connected to the radio frequency detector and is capable of producing an electrical signal waveform in the audio frequency range to generate the audible tone. The speaker system is connected to the voltage-to-frequency converter circuit, wherein the speaker system outputs the audible tone, with pitch of the tone related to the strength of the radio frequency signal.