1 Telecommunication Adapter For Hearing Aid Wearers - with extensions M. Finke, D. Bauer, A. Plinge Institut für Arbeitsphysiologie an der Universität Dortmund Ardeystraße 67, 44139 Dortmund, Germany Tel. +49-231-1084-250 ; Email: finke@arb-phys.uni-dortmund.de Keywords: hearing impaired, telecommunication, mobile phone Abstract. Modern communication technology - if not adapted to the needs of the severely hearing impaired person - leads to the exclusion from everyday communication. Only if it is well adapted it may offer a higher degree of freedom and integration. A telecommunication adapter was developed and can be used for two purposes: to provide access to mobile phone technology, and - with extension – to high quality access to PSTN phones. At the same time connections to TV, radio and other external sources are made possible. 1. INTRODUCTION: USER NEEDS IN TELECOMMUNICATION The approach below is the result of a follow-up study of the EU project MORE (Mobile Rescue Phone). Here we are trying to combine the practical implications of the foregoing research to transfer research into a practical aid. Being connected or not When the needs of hearing impaired persons are discussed, it soon becomes obvious that different auditory losses require different ways of compensation. People with sensory losses, which are progressing from moderate to severe do suffer from an increasing degree of being cut off from communication (cp. figure 1). Problems arise both in face-to-face personal communication and in speech telecommunication. The auditory isolation from the world’s communication is a barely tolerable handicap when the new possibilities of technology in the information / communication age are taken into consideration. Problems with PSTN With the advent of the new telephone generations, with a much improved acoustical quality for the non-hearing impaired user, the possibility of using an inductive coupling between telephone and hearing aid has been eliminated. The user has fallen back onto the use of acoustical coupling, which has two main disadvantages: As the properties of the coupling can barely be controlled by the user, the speech signal of the hearing aid will change its quality in an unpredictable way. Ambient noise is being picked up deliberately and mixed with the speech signal. A reduction of speech intelligibility will often be the result. Depending on their residual hearing ability, the user will be unable to understand the