User Manual

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If your hearing device happens to be vulnerable to
interference, you may not be able to use a rated
mobile device successfully. Trying out the mobile
device with your hearing device is the best way to
evaluate it for your personal needs.
M-Ratings: Wireless mobile devices rated M3
or M4 meet FCC requirements and are likely to
generate less interference to hearing devices than
mobile devices that are not labeled. M4 is the
better/higher of the two ratings. M-ratings refer to
enabling acoustic coupling with hearing aids that
do not operate in telecoil mode.
T-Ratings: Mobile devices rated T3 or T4 meet
FCC requirements and are likely to generate
less interference to hearing devices than mobile
devices that are not labeled. T4 is the better/
higher of the two ratings. T-ratings refer to
enabling inductive coupling with hearing aids
operating in telecoil mode.
Hearing devices may also be rated. Your hearing
aid manufacturer or hearing health professional
may help you nd this rating. Higher ratings mean
that the hearing device is relatively immune to
interference noise. Under the current industry
standard, American National Standards Institute
(ANSI) C63.19, the hearing aid and wireless mobile
device rating values are added together to indicate
how usable they are together. For example, if a
hearing aid meets the M2 level rating and the
wireless mobile device meets the M3 level rating,
the sum of the two values equals M5.