Verykool R25 - Manual (Page 24)

likely to be more
usable with a hearing aid’s telecoil than phones that are not rated.
T4 is the better/higher
of the two ratings.
R25 is rated T3.
Please power off the Bluetooth function while using hearing aid
devices with your R25.
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.
Safety and regulatory guide
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 better use. A sum of 8 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. This
methodology applies equally for T ratings. 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
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