Personal frequency modulation (FM) systems are wireless, radio devices for transmitting speech from a distance. The range reaches up to 100m in open space, in closed space significantly less. It consists of a transmitter and one or two receivers, transmitting a signal to the hearing aid. This device is dedicated mostly for pupils, students, conference participants and people attending small group meetings. FM systems may also be used in poor sound environments, like in a car or a train.
These systems are versatile and may be paired with hearing aids of various producers, meeting some conditions first. When the producer of a hearing aid and the FM system is the same, additional functions facilitating its operation may be available. It is the only assistive listening device partially refundable by the National Health Fund.
How is FM system built?
Transmitter — its task is to capture and send a radio frequency speech (or music) signal to the receiver(s) paired with hearing aids. The transmitter should be worn or positioned close to the speaker to let the voice be directly picked by the microphone. FM system usually has the ability to be connected to the audio source (TV, computer, radio) with a cable. Advanced devices may be also paired with above devices over Bluetooth technology.
- Receiver — is to receive a signal from the transmitter and pass it directly to the hearing aid or via an additional device paired with the hearing aid.
FM systems are recommended for people who, despite the use of hearing aids have some difficulties keeping up with conversations with one or more people, especially in noisy surroundings, like lecture halls, restaurants, classrooms.
Content by Phonak