Semin Hear 2003; 24(1): 029-042
DOI: 10.1055/s-2003-37907
Copyright © 2002 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel.: +1(212) 584-4662

Telecoils: Principles, Pitfalls, Fixes, and the Future

Jerry L. Yanz, David Preves
  • Micro-Tech Hearing Instruments, Inc., Plymouth, Minnesota
Further Information

Publication History

Publication Date:
13 March 2003 (online)


This article will review the principles of inductive coupling for hearing aids, upon which telecoil success depends. The authors will explore some of the design issues that have been solved in the past, others that are just now approaching solutions, and still others that will depend on the success of current and ongoing development efforts. Use of inductive coupling for bringing the telephone signal into hearing aids via a telecoil, in comparison with acoustic coupling, has the advantages of reduced acoustic feedback and environmental noise problems. Inductive coupling, however, may have difficult-to-remove interference pickup from electromagnetic signals produced by common objects. In recent years, the effectiveness of inductive coupling has been helped greatly by adding an integral preamplifier to the induction coil assembly, multimemory programmable hearing aids with a dedicated memory for telephone use, and knowledge of how to best position the telecoil within the hearing aid. Innovative features such as the automatic telecoil switch have made listening via telecoil even easier by eliminating the need to switch modes manually. Future improvements for coupling telephones to hearing aids may incorporate wireless technologies other than induction.


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