User guide
A
N EDUCATOR’S GUIDE
•
59
It is important to know when it is appropriate to
turn off the transmitter as well. Children wearing an
FM should not be able to hear private conversa-
tions their teacher is having with another student,
teacher, or any discussion that is not related to the
classroom presentation. They should especially not
be able to hear trips to the bathroom! Remember
to turn off the transmitter when leaving the room.
Considerations for coupling FM systems to
cochlear implant sound processors include the
following:
• Cochlear recommends that a child be able to
reliab
ly report problems with sound quality
pr
ior to a personal FM system being fit.
• The radio frequency (RF) that the externall
y
worn sound processor uses to transmit data to
the internal (implanted) part of the system can
be picked up by the FM system,
introducing
noise interference.
• The output of the FM system may be higher or
lower than optimal for the sound processor
(therefore requiring adjustment by the
audiologist).
Alter
natively, or in addition to this,
the level of the sound processor microphone
may be too high to allow the FM signal to
predominate
,
or too lo
w to allo
w the child to
monitor his/her own voice or hear his/her
classmates. These settings are individual to
each child.
• The child may experience poor sound quality
due to environmental interference such as
fluorescent lighting,
computer equipment,
or
metal barriers, to name a few. Decisions must
be made about situations in which FM use is
pref
er
red. In addition, noise management
techniques can be programmed into the sound
processor for the child who is able to manage
the use of more than one progr
am in the
device. These techniques are referred to as
SmartSound technologies.
• Personal FM equipment can be a challenge to
manage, as well as troubleshoot.
• With training and experience, these systems can
provide a high level of speech understanding for
a child with a cochlear implant, well above what
can be achieved by listening through the sound
processor alone
This guide includes compatibility charts for various
FM systems that have been tested for compatibility
with Nucleus sound processors. When using patch
cables to connect body worn sound processors to
FM receivers, keep the two units as far apart as
possible to reduce the possibility of interference.
The ideal f
itting and verification procedure for using
a per
sonal FM system with a cochlear implant
sound processor is descr
ibed below. This
procedure can be performed in a test booth, or,
more ideally, in the typical classroom environment.
This testing may need to be accomplished over
more than one session.
1. With test materials appropriate for the child’s
abilities, test the child’s speech recognition
(auditor
y onl
y, no visual cues) in quiet through
the sound processor alone, in the environment
in which the FM system will be used, at a typical
distance from which the teacher will speak.
2. Next, test the child with the FM system attached
to the sound processor.
a.
Star
t with all equipment tur
ned off.
b. Turn on the FM transmitter.
c. Attach the FM receiver to the sound
processor (see individual processor man
uals
for instructions on connecting external
accessories).