The purpose of this work is to develop a classroom amplification system based on digital 900 MHZ cordless technology. The need for such amplification systems arises because of the large number of students in regular classrooms with transient hearing losses due to otitis media, and the even larger number of special needs classrooms effected by the same problem. Recent studies indicate that, on the average, 25% to 30% of children in primary schools will have this such hearing deficits at any given time, although only a very small percentage of these will be classed as hearing impaired. For special needs classes, the number approaches 75%. Data gathered by the National Center for Health Statistics indicates that this problem increased by at least 45% between 1981 and 1988 for children 15 and under, and by 224% for children age 2 and under. It is clear that because of interference problems inherent in the usual form of FM Radio communication systems, that the present methods used in classrooms cannot be used in more than a few rooms of any given school before serious interference problems occur. The large development funds available to the telephone industry has enabled them to develop and market extremely advanced technology in 900 MHZ cordless phone at very low cost. These phones are far superior to other FM systems at eliminating interference. Purchasing and re- manufacturing such phones for use in classrooms opens the technical possibility of amplifying virtually all classrooms at ver modest cost.
This device has extensive market potential in over 2,000,000 US classrooms alone. It also has great potential for portable amplification systems.
