Radio Frequency systems capture audio via a microphone of line-in connected to a transmitter broadcasting the radio signal via an aerial. An aerial connected directly to the transmitter via a coax cable or can be wall mounted for better coverage.
RF systems cover large areas and are used in a wide variety of public places.
Users require an RF receiver and earphones or a neckloop to connect directly to their hearing aid or cochlear implant (CI). Some receivers are pre-set to a fixed channel. Other systems consist of tuneable receivers which can be set to any one of 8 or 10 channels for use in locations where several transmitters are broadcasting on different channels.
FM radio can be affected by external radio interference. There are only a limited number of channels available in the UK leading to limited availability.