SEHT SH40-80 USER MANUAL Edition 3
Page 3
Using the SH40-80
The SH40-80 uses state-of-the-art technology to reduce exterior noise and promote clear
in-flight communications reducing user fatigue.
Once the ANR power switch is activated the SH40-80 reduces unwanted ambient noise
through Active Noise Reduction (ANR). This is done by placing a microphone inside the
ear cup and generating an anti-noise signal through the speakers.
The anti-noise and the ambient noise cancel each other out before they reach the ear
resulting in a quieter environment. Through this technology low frequency ambient noise
is significantly reduced making communication easier and reducing user fatigue.
The SH40-80 will continue to operate as a standard passive aviation headset should the
ANR become inactive for any reason such as low or no battery power.
Getting started
Correct fitment is essential to ensure the correct operation of any headset. A good seal
around your entire ear and a symmetrical fit across the top of your head is necessary to
ensure the correct performance of the ANR feature.
The following steps will assist you in achieving the proper fit:
1. Extend the ear shell slider adjusters fully.
2. Place the headset on your head and compress the sliders slowly on each side
until the head pad rests softly on the top of your head.
3. Adjust the ear cups to ensure the ears are fully inside the ear seal and there is
uniform pressure on your head
4. Tighten the adjusters securely to prevent unwanted movement.
IMPORTANT
If the headset is not fitted correctly this may generate an oscillating noise, this is caused
by the ears seals not sealing entirely around the ear, adjust the ear cup and ear seal to
make sure the ears are sealed completely. The wearing of glasses can promote the
issue and if experienced it is recommended to use with cotton ear seal covers (available
separately) to reduce this.
The microphone can be rotated and placed on the right or left side of the headset. To
adjust the microphone placement rotate the microphone from its base and bend the
flexible boom. For clear and crisp communication, the microphone should be placed
approximately 3mm from the lips.
Battery Type
The SH40-80 uses two AA batteries (supplied). Always use good quality alkaline
batteries to ensure the best performance. DO NOT use rechargeable batteries as they
provide reduced and uneven voltage which can interfere with the correct headset
performance.