
HEADSET OPERATION
1.
Rotate the flexible boom overhead to wear the microphone on either the right or left side of
the head.
2.
Rotate the headset volume control (on the side of the headset opposite the microphone
boom) fully counter-clockwise to the minimum position. before the headset plug is inserted
into the aircraft or intercom
3.
With the headband resting securely on the top of the head, check that the earseal are
centered over the ears.
4.
For best noise cancellation, position the microphone 0-6 mm from your lips .
5.
Insert the plug
(M642/2-2)
into the aircraft or intercom jack.
6.
Volume Adjustment Procedure
Rotate the headset volume knob clockwise to a comfortable level.
HEADSET NOISE ATTENUATION DATA
The noise reduction or attenuation characteristics of communication headsets must be measured
according to an accepted standard procedure if the characteristics of different headset are to be
compared in a meaningful way.
The Noise Reduction Rating (NRR) is provided in accordance with U.S.EPA Regulation 40 CFR
Part 211.Subpart B. The Range of Noise Reduction Rating for Existing Hearing Protectors is
Approximately 0 to 30. (Higher Numbers Denote Greater Effectiveness)
Frequency[Hz]
125 250 500 1000 2000 3000 4000 6000 8000
Attenuation[dB]
14.3 21.5 27.1 31.8 36 39.5 41.3 39.7 37.0
Standard Deviation
3.3 2.4 1.5 1.6 1.3 2.1 2.1 2.0 1.3
Cautions:
1: Proper Fit
Proper fit is critical to its noise attenuation effectiveness.
A: Push the headband down until it rests comfortably on the top of your head. Move
the earcups slightly up or down or from side to side until you feel Maximum
attenuation.
B: The use of eyeglasses will reduce the attenuation. Use thin temples on your glasses
to keep noise leakage at a minimum.
2: Use in Impulsive Noise Area
NRR is based on continuous noise, may not be an accurate indicator of
the
impulsive noise such as gunfire.
For maximum protection, you can use ear plugs in addition to it.
3: Maintenance and Cleaning
In order for your headset working properly, always comply the following:
A: Never alter your headset.
B: If you see a defect such as splits in cups, seek immediate replacement.
4: Cleaning Instructions
A: Do not immerse in water.
B: Clean regularly with mild soap water. Sponge off headpad and earseals, Taking care
to rinse thoroughly.