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5
OPERATION
Electronic noise cancellation is an “electrical” process. Power to drive the circuitry
is obtained from either the Portable Battery Power Module (models ending in “XL”
or “X”) or the aircraft’s electrical system (models ending with “XP”).
XL-9V
Instructions
Introduction
The model XL-9V battery pack uses a
9 volt alkaline battery to provide power
to the headset ENC system. The XL-9V
features an Auto Shut Off function to save
the battery if the power switch is left on
when the headset is not in use. The Auto
Shut Off feature operates by sensing loss
of microphone DC bias voltage when the
headset is unplugged or aircraft audio
system is shut off.
A switch is provided inside the battery
compartment (see Fig.1) to control the
Auto Shut Off feature.
The XL-9V is
shipped from the factory with the switch in the DISABLE position,
which will provide continuous power to the ENC system whenever
the power switch is on.
GENERAL AVIATION PORTABLE BATTERY MODULE