Utstar pn820 User Guide

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C

H

10

Hearing devices may also be rated. Your hearing device manufacturer 
or hearing health professional may help you find this rating. Higher 
ratings mean that the hearing device is relatively immune to 
interference noise. The hearing aid and wireless phone rating values 
are then added together. A sum of 5 is considered acceptable for 
normal use. A sum of 6 is considered for best use.

In the above example, if a hearing aid meets the M2 level rating and 
the wireless phone meets the M3 level rating, the sum of the two values 
equal M5. This should provide the hearing aid user with “normal usage” 
while using their hearing aid with the particular wireless phone. “Normal 
usage” in this context is defined as a signal quality that is acceptable 
for normal operation.

The M mark is intended to be synonymous with the U mark. The T mark 
is intended to be synonymous with the UT mark. The M and T marks 
are recommended by the Alliance for Telecommunications Industries 
Solutions (ATIS). The U and UT marks are referenced in Section 20.19 
of the FCC Rules. The HAC rating and measurement procedure are 
described in the American National Standards Institute (ANSI) C63.19 
standard.

For information about hearing aids and digital wireless phone