DEVICES to Help you Hear - (ASSISTIVE DEVICES)Two problems people with hearing loss face when trying to communicate:
A. DISTANCE (between the speaker and the listener) B. BACKGROUND NOISE Both of these problem areas can be overcome to a greater or lesser degree with Assistive Listening Devices (ALDs) and other technology. Assistive Listening Devices - types of systems Hard-wired System Loop System FM System Infrared System Assistive Listening Devices - basic information All of the above systems have their own unique advantages and disadvantages. However, they all share certain of the same elements - these are:
Once the signal has arrived at the person using the system to hear better, then the signal must somehow be received at the person's ears. This can be done via headphones or a T-switch (within a hearing aid or cochlear implant). NOTE: see below for more about the T-switch Some examples of where or under what circumstance a system might be used A hard-wired system might be used when a speaker and a listener are close to each other, but in a noisy environment, such as a moving car or a restaurant. Here, the speaker would speak into the microphone and the signal (i.e. speaker's voice) would be conveyed to the speaker along an electrical wire. The hard-of-hearing (HoH) listener would set the volume of the amplifier at a level that is comfortable for him. Finally, the signal would be be introduced into the HoH person's ears via either headphones, ear buds, or a neckloop (if the person has a hearing with a T-switch). A Pocker-Talker or Sound Wizard are examples of this type of technology. At a large meeting, a Loop system might be used. This is a very convenient system when a number of HoH people (who have hearing aids equipped with T-switches) will be present The speaker speaks into a microphone; the signal is boosted via the amplifier and the signal goes into a Loop of wire that covers the perimeter of the meeting area (or at least a portion of it). This Loop puts out an electro-magnetic field that can be picked up by either: a) a hearing aid's T-switch or b) a device with magnetic field pick-up capabilities that can then be used to send the sound into headphones for a person who does not have hearings with a T-switch. Also used in a large meeting environment are FM systems and Infrared systems. Systems specifically built for TVs can be of any of the above types. T-switch There is a characteristic in electricity which refers to the phenomenon that, when a circuit carrying a signal is brought in close proximity to another circuit, that signal will be "induced" into this latter circuit. A T-switch on a hearing aid refers to a telecoil (or circuit) within the aid that is capable of picking up the signal from a telephone or Loop system or a neckloop. This technology has been around for decades, but it is still being used very effectively today. It is advised that every hearing aid and cochlear implant should come equipped with an effective telecoil and related T-switch. Captions An assistive technology that does not rely upon amplification of sound are Captions. With this technology, the spoken word (and sounds) can be displayed in written language. Captions may be done beforehand, as in Closed Captions on TVs and Open Captions for some movies. There is also Realtime Captioning that is basically done at the time that the words are being uttered, as in a meeting situation or a live performance. |