Abstract: An interface between a portable cellular phone and an automobile radio to allow hands-free operation of the phone is housed in a remote housing connected to a battery eliminator cigarette lighter adapter plug for simple installation into an automobile. The interface converts incoming signals from the cellular phone from audio frequency to radio frequency and transmits the signals to the existing automobile radio receiver, wherein the signals are reproduced over the radio speakers. The interface may also be used with a power conversion system to increase the power of the phone transmissions. Further, the interface may be used with any external communication source, such as a facsimile machine or laptop computer and modem. The interface is also easily adapted for use with any stand-alone audio producing devices, such as a cassette deck or compact disc player.