Telecoils: Issues and Relevancy

ABSTRACT

What a hearing aid user hears through a telecoil via inductive coupling is as important as what he or she hears via the microphone, yet many audiologists and the hearing aid industry in general have not put much time and energy into either the advancement of telecoil circuitry or the proper fitting of the circuit. Coupling techniques for telephones as well as for assistive listening devices are discussed in this article. ANSI standard S3.22 (1996) is described and methods for telecoil evaluation are presented. The current status of telecoils for both telephone communication and as assistive listening system receivers is reviewed.

KEYWORDS

Telecoil - induction coil - electromagnetic energy - telephones - assistive listening devices

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