1	Demystifying Assistive Listening Devices: The Devil is in the Detail
2	PEPNet Regional Centers http://www.pepnet.org
3	Agenda Benefits Components Wireless systems Troubleshooting Keys to success
4	Why use assistive listening devices? Why aren’t hearing aids enough? What do hearing aids do? sounds > sounds What do ALDs do? sounds > sounds ADA mandates effective communication
5	Components Individual Sound Environment Sound Source Microphones Transmitter and Receiver Systems Coupling Devices Telecoils
6	Components: Individual Hearing loss binaural or monaural severity (dB) and frequency (Hz) conductive or sensorineural may fluctuate or be progressive Age at onset of loss Acceptance of loss Speech reading ability Hearing aid/T-coil use Knowledge of and comfort with ALDs
7	Components: Sound Dimensions Frequency Loudness Impact on Speech Intelligibility Distance Signal-to-Noise Ratio Reverberation
8	Speech Sounds: Frequency & Loudness
9	Components: Environment Light or dark Uncovered windows Distance from speaker Room acoustics and noise
10	Components: Sound Source Instructor giving a lecture Panel of speakers Video or audio recording Q&A from the audience Hard of hearing student Neighboring student
11	Communication Tips Face-to-face communication Maximal lighting conditions Don’t yell Be patient Don’t be afraid to write
12	Components: Microphones Omnidirectional Unidirectional Lavaliere or Lapel Table top or conference Environmental mic Placement is vital! Remember effect of distance on sound
13	Components: Transmitter and Receiver Systems FM Infrared Electromagnetic induction loop Hardwired systems
14	Components: Coupling Devices No hearing aid OR no T-coil headphones earbuds Hearing aid with T-coil neckloop silhouette headphones Other methods Direct Audio Input FM Boot Cochlear implants
15	Components: Telecoils Hearing Aids: Microphone vs T-coil Not all hearing aids have T-coils T-coils are not as sensitive as hearing aids Proximity is important Commonly found in telephones and speakers Susceptible to electromagnetic interference
16	T-coils & Couplers & Mics! Oh My! Encourage T-coil purchase and usage. Inform students about the possibility of a Mic/T/Both switch. Make environmental mics available. Experiment with different coupling devices.
17	FM Uses radio waves Transmitter a radio station Receiver a radio Crib Monitor
18	True or False? You can leave the room and still hear the presentation. This system can be used indoors or outdoors. You must have a receiver to use this system. You must have a hearing aid to use this system. You can use FM in multiple rooms in a building. I can use my FM receiver with your FM transmitter.
19	FM Advantages Very portable Very easy to set up and use Offers great flexibility of movement Used indoors or outdoors Appropriate for mild to profound losses Receiver can be covered or put in pocket No fluctuation in strength of signal
20	FM Disadvantages Receivers are required for everyone Receivers vary in quality and durability Potential for outside interference 72-76 MHz bandwidth allotted by FCC police band, construction walkie talkies, pagers Receivers and transmitters must be on the same channel There must be 1 free channel between systems used in close proximity
21	Infrared Uses infrared light Transmitter-emitter panel like the infrared diode on a remote control emits signal in 60 degree cone-like a flashlight Receiver like the infrared receiver area on a TV or VCR TV headphones
22	True or False? You can leave the room and still hear the presentation. This system can be used indoors or outdoors. You must have a receiver to use this system. You must have a hearing aid to use this system. You can use infrared in multiple rooms in a building. I can use my IR receiver with your IR transmitter.
23	Infrared Advantages Compatibility: 95 kKz is industry standard Home receivers can be used with public transmitters 250 kHz if high intensity lighting No spillover means security Can be used in adjacent rooms Widest bandwidth and best sound reproduction Appropriate for mild to moderate/severe loss Not affected by radio transmission
24	Infrared Disadvantages Receivers required for everyone Must have direct line of sight Can’t cover the receiver or put in pocket Indoor or evening use only High intensity or fluorescent lights cause interference Large areas require multiple emitter panels Quality varies with company
25	Electromagnetic Induction Loop Uses electromagnetic fields of energy Power lines Transmitter-Loop of several wires Receiver T-coil in hearing aid desktop receiver Telephone and other speakers As small as a neck loop or as large as an auditorium
26	True or False? You can leave the room and still hear the presentation. This system can be used indoors or outdoors. You must have a receiver to use this system. You must have a hearing aid to use this system. You can use induction loops in multiple rooms in a building. I can use my loop receiver with your loop transmitter.
27	Induction Loop Advantages Low equipment costs after installation Easy operation Lasts forever Induction receivers are compatible with ALL loop systems Unobtrusive with T-coil hearing aid
28	Induction Loop Disadvantages Installation costs may be high Installation may not be possible in historic buildings Can’t assume everyone will have a T-coil Susceptible to electrical interference and spill over Must sit around looped area May be dead areas within loop
29	Troubleshooting: General Batteries charged? Deductive reasoning T-coil working? try it out with a phone call try different couplers Ultrasonic sensors Check with local SHHH group Cultivate an expert Call the company!
30	Troubleshooting: FM Are the receiver & transmitter on the same station (frequency)? Color code or number them What sources of interference are close by? Station drift-your system OR someone else’s police band, construction walkie talkies, pagers Must have one free channel difference if 2 different stations are being used in rooms next to each other.
31	Troubleshooting: Infrared Is the room bright, or is direct sunlight present? Is anything blocking the line of sight? Are high intensity fluorescent lights present?
32	Troubleshooting: Induction Loop Are there sources of electrical interference and spillover nearby? Portable systems can be a mobility hazard. Are wires protected?
33	Keys to Success for the Speaker Avoid drawing attention to the individual user Repeat questions from the audience Place mic close to mouth (or other sound source)but NOT in front of the mouth Use an unidirectional mic when possible Turn off or step away from overhead when not in use Do not direct their attention away from your face, and then start talking!
34	Keys to Success for the Speaker Repeat questions from the audience Rephrase instead of repeat Don’t stand in front of windows or bright lights Face your audience when speaking Avoid talking while the class is retrieving materials
35	Keys to Success for the Student Batteries charged and T-coil working Proximity to T-coil Proximity to interference just changing seats may help Continue to sit within 20 ft. of the speaker if you will use speech reading Interact with others about coping techniques-SHHH, Beyond-Hearing
36	Keys to Success for the Student Make sure the volume is down when you first put the coupler on Experiment with different couplers, locations, and environments Get an environmental mic or hearing aid with mic/t/both position Check out equipment ahead of time While you are at it, check out the instructors too! Be specific
37	Keys to Success for the Service Provider Cultivate an expert for troubleshooting Always check out the system ahead of time Experiment Encourage users to experiment Show how ALDs can be unobtrusive Advertise that the systems are available If the user isn’t ready yet SHHH or ALDA meetings or web sites e-mail lists like Beyond-Hearing provide a fact sheet on the devices available from your program provide info about impact of distance, room noise on understanding
38	Review Consider the individual first. Evaluate the requirements of the setting and the properties of the equipment. Buy equipment from companies that will help you troubleshoot. Don’t forget the non-electronic communication tips!
39	Contact Information Cheryl D. Davis, Ph.D., Coordinator WROCC Outreach Site at WOU Regional Resource Center on Deafness Western Oregon University Monmouth OR 97361 503-838-8642 (v/tty) 503-838-8228 (fax) wrocc@wou.edu http://www.wou.edu/wrocc