Listening Aids
What is a radio aid?
Radio Aids and Cochlear Implants
Benefits of using a radio aid
Potential problems
Where can I get a radio aid?
Induction Loop Systems
Accessing Audio from a PC
Classroom Soundfield Systems
Choosing and installing a Soundfield System
Listening Aids for non-hearing aid users
Useful Links
What is a radio aid?
In crowded situations or when a voice source is more than arms length away, hearing aid users can find background noise levels are as loud as the voice they want to hear.
A radio aid system greatly improves the clarity of sound by allowing a human voice to be fed electronically into a hearing aid reducing
background noise and sound loss between speaker and listener.
Radio Aids (also known as personal FM systems) have two main components: a transmitter and a receiver. The person who is speaking (usually the lecturer) wears the transmitter. A microphone picks up his or her voice.
The sounds are transmitted by an FM radio signal to the receiver, which is worn by the student. The receiver converts the signal into a sound that the student can hear.
Radio aids are usually used in conjunction with the student’s hearing aids. There are a number of ways in which the radio aid inputs the sound signal to a hearing aid.
- ‘direct input’ to the hearing aids either using a lead or plugging directly into the hearing aid (in the case of miniature receivers, sometimes called ‘sugarcubes’ suck as the Phonak Microlink.
- a neck loop connected to a radio aid receiver
Radio aids are also beneficial for students who have cochlear implants. The radio aid is connected to the implant using a dedicated lead.
Portable neck loop devices such as the popular RNID Conversor is an inexpensive and simple-to-use alternative.
Phonak, manufacturers of hearing technology, have an informative presentation on their website which explains what a radio aid does and why it is helpful, particularly in educational environments. The tutorial comprises of a slide show accompanied by a presentation by an audiologist. The tutorial has chapters (like a DVD) so you can skip to sections that interest you most. Have a look at the tutorial by clicking on the following link: www.hearingseminars.com/introductiontofm.
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Radio Aids and Cochlear Implants?
The cochlea is the auditory part of the inner ear. A cochlear implant (CI) is a surgically implanted electronic device that provides a sense of sound by directly stimulating any functioning auditory nerves inside the cochlea with electrical impulses. CI users can benefit from using radio aids.
There are specific models (e.g. the Phonak MicroLink Freedom) that have been specifically designed for students with a CI. To determine the correct radio aid for a CI user, it is essential to consult the student’s audiologist and/or the cochlear impant clinic for advice. These specialist staff will also be able to fit and programme the radio aid. The ci-4teenz website (link below) is an excellent visual introduction to how a CI works and how students can get the best from their CI.
Benefits of using a radio aid
A general principle is that if a student uses a hearing aid, then he or she is also likely to find a radio aid helpful in classroom situations.
Radio aids help overcome difficulty hearing in a classroom by:
- Making the speaker’s voice stand out from background noise
- Effectively maintaining a constant distance between the speaker and the listener
- Reducing the impact of unhelpful reverberation (echo)
Radio aids are very light and portable, can be controlled by the student and used in any room.
Radio aids are more effective than induction loop systems, do not require installation and are less susceptible to interference.
‘FM Advantage’, a booklet detailing procedures for setting up fm radio aid systems for use with hearing aids is available from Connevans. For more information email fmadvantage@connevans.com.
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Potential Problems
If the radio transmitter (the part that the tutor wears) is not switched off, students may be able to hear conversations that they are not supposed to hear!
Loose jewellery or clothing can knock or brush against the microphone and cause noise. You can avoid this problem completely by using a headset microphone, an added benefit is that they also maintain a constant distance between the speaker’s mouth and the microphone.
Radio aids can be sensitive devices and should be checked regularly. Learning how to check for faults is relatively simple. If a student is not receiving a signal, check the following:
- Do the batteries need replaced or recharged?
- Are the transmitter and receiver set to the same frequency?
- Is the student’s hearing aid on the correct setting?
- Are the cables loose?
- Do the shoes (adaptors for attaching a receiver onto a hearing aid) fit properly?
- Are the shoe contacts broken?
- If it still isn’t working, contact the supplier for support
example of a shoe
Radio aids have often been seen as the solution to poor acoustics in the classroom. However, it must be noted that they only partially solve the problem; improving access to spoken information must also involve addressing the classroom management style and classroom acoustics.
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Where can I get a radio aid?
- If the student is studying at HNC level or above (HND, Degree etc) he or she can apply for Disabled Student’s Allowance which may provide funding to buy specialist equipment like radio aids. To apply for this money, the student needs to see a DSA Assessor and/or an Audiologist.
- Your college may already have radio aids or other listening technology. Ask about this when you apply for a course. Ask your college BRITE link, this is someone who is trained and experienced in providing support to students who have additional support needs. You can find a list of these people on the BRITE People Page.
- If your college is a member of the BRITE Equipment Loan Bank, a member of staff can borrow radio aids on your behalf for up to 3 months. This is so that you can try them out and help the college to decide whether to buy some radio aids.
- If you are thinking of buying radio aids, have a look at the range of one of the big suppliers, like Connevans or the RNID.
- The NCDS Loan Bank will lend out radio aids and other listening devices for up to 3 months to people under 25 who are in full-time education.
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Accessing Audio from a PC
Increasingly, colleges are creating and using multimedia resources, particularly in their virtual learning environments. Multi-sensory delivery can be both engaging and inclusive, but if a student uses hearing aids, accessing the audio might be difficult. Ideally, audio content should be available in text format too, but often a student may wish to access the audio directly.
Standard headphones are not suitable for a student who wears hearing aids as headphones will likely be uncomfortable and do not provide the kind of audio output the hearing aid needs.
The first and most effective option is direct input leads which feed the audio directly from the computer into the hearing aid. The student will need assistance from his or her audiologist to get these set up.
Alternatively, the student can be provided with a personal inductive loop that can be connected directly to the headphone jack in the computer (thus these loops can also be used anywhere you can use 'personal-stereo' type headphones). The student wears the loop around the neck, or hooked on the ears, depending on the model of loop and switches their hearing aid to the 'T' position. The audio from the computer is then directly input to the hearing aid(s). These personal loops are relatively inexpensive at around £30. You can get a more detailed explanation of how the loops work and an idea of prices from Connevans (link below).
Induction Loop Systems
This is an area of hearing technology that many people are familiar with from in theatres, cinemas and on reception desks. It is usually activated by setting a switch on the hearing aid to the “T” position.
An induction loop system has a sound input (usually a microphone), an amplifier and a loop of cable which is run around the area in which the system is to be used. The loop generates an electromagnetic field which is picked up by the telecoil in the hearing aid. The hearing aid user will hear the sound while they are within the looped area.
In the UK, loops are now rarely used in a classroom setting. Alternatives such as radio aids and soundfield systems offer improved and more consistent sound quality and are less susceptible to interference. Induction loop systems can also be difficult to use in multiple applications, as the signal from one area can overspill into another.
 portable induction desk loop system
In educational settings, loops should be considered in:
- lecture theatres
- performance spaces
- meeting rooms
- reception area desks
This is primarily for visitors to the college rather than for deaf students themselves, who should have their own listening equipment, although loops are also useful for students who are waiting for an appointment with an audiologist or on equipment being delivered/returned after repair.
Loop systems require specialist maintenance and should be checked regularly. For further information and pricing details, contact the main suppliers.
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Classroom Soundfield Systems
This ‘whole class’ inclusive technology (also termed ‘soundfield amplification’) ensures that the signal level of speech is delivered to all parts of the classroom at an appropriate level above the background noise. This technology is of benefit for everyone in the classroom, not just the hearing aid user.
Soundfield systems provide an even spread of sound throughout a classroom and allows all the students to hear equally well wherever they are seated and whichever direction the teacher faces.
A system consists of a transmitter with a microphone, a receiver/amplifier and 4-6 speakers. The lecturer wears a transmitter usually with a collar worn microphone.
The lecturer’s voice is amplified at a low level (5-10dB) and is projected round the room from speakers mounted above head height. Wall mounted speakers are usually included in a soundfield system kit.
These systems are not a substitute for radio aids, but they can be used with a student’s radio aid to get a high quality level of sound input.
The system can also be integrated with multimedia sound. It is also important to note that whole class technology is not a substitute for remedying poor classroom acoustics.
A soundfield system benefits the tutor by offering reduced vocal fatigue, improved class control and attentiveness. For flexibility in teaching style a choice of microphones are available.
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Choosing and installing a soundfield system
- The supplier should provide installation, information including operating instructions and ongoing support. Most offer a trial evaluation period.
- Large rooms or rooms that are unusually shaped will usually need specialist advice. Lecturers must receive adequate training in using the systems.
- The distribution of loudspeakers and their directional characteristics is a key issue in achieving high speech intelligibility. Seek specialist advice when installing a system.
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Listening Aids for non-hearing aid users
Some students may have a degree of hearing loss, but do not use hearing aids. Perhaps their hearing loss is temporary, or they are waiting to see an audiologist.
There are products designed especially for this user. Many of these products are designed for home use, for instance, listening to the television and are not as powerful or as complex as radio aids designed for use with a hearing aid.
Sound is input directly to the ears using headphones or stetoclips, which are headphones that hang under the user’s chin, like the ear pieces on a medical stethoscope. For hygiene reasons, students should be given or bring their own headphones for use with these devices. Miniature, in-ear devices are also staring to become available, such as the Phonak Edulink.
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Useful Links
http://www.brite.ac.uk/participants.htm: BRITE Links
http://www.connevans.com : Connevans online catalogue, featuring a wide range of listening technology including soundfield systems
http://www.ndcs.org.uk : Deaf Friendly Schools – Clara Ratcliffe (2001) NDCS. Available for download as a PDF
http://www.ndcs.org.uk :Personal/Infrared listening aids for children and young people (2005) NDCS. Available for download as a PDF
http://www.pcwerth.co.uk : PC Werth Soundfield Systems
http://www.phonak.com : Phonak
http://www.ndcs.org.uk : Radio Aids - an introductory guide (2005) NDCS. Available for download as a PDF
http://www.rnid.org.uk : RNID back to top |
