M-169A/AIC is a dynamic, noise-canceling moving coil microphone designed for use in an oxygen mask or pressure-type oxygen helmet, at altitudes where the use of an oxygen helmet is required. The microphone element is intended for use with intercommunication sets AN/AIC-10( ) and AN/AIC-18. The microphone is used with both the MBU-12 and MBU-20/P (Combat Edge) oxygen masks.

The microphone assembly shall be tested in accordance with the tests listed in table II. TABLE I. Part Number Designations

Part or Identifying Number (PIN) Characteristics ------------------------------------------------------------------------------- M-169A/AIC Microphone assembly as shown above. M26542/12-01 Pass-through connector, alone.

[A circle]TABLE II. Parameter applicability

Inspection Requirement Test Qualification Group Group Group paragraph paragraph tests "A" "B" "C" tests tests tests ---------------------------------------------------------------------------------------------------------------- Group I Visual and mechanical inspection 3.1, 3.4, 3.5 4.5.1 X X Sensitivity at ground level 3.5.1 4.5.2.2 X X Sensitivity at altitude 3.5.2 4.5.2.3 X Frequency response at ground leve 3.5.3 4.5.2.4 X X Frequency response at altitude 3.5.4 4.5.2.5 X Impedance 3.5.5 4.5.3 X X Noise cancellation characteristics 3.5.7.1 4.5.5.1 X Effect of external magnetic field 3.5.8 4.5.6 X Stray magnetic field 3.5.9 4.5.7 X Linearity 3.5.10 4.5.8 X Talk-out 3.5.11 4.5.9 X X Dielectric withstanding voltage 3.5.12 4.5.10 X Signal-to-noise 3.5.7 4.5.5 X X Distortion 3.5.6 4.5.4 X X Interchangeability 3.5.13 4.5.11 X X Group II Thermal shock 3.5.14 4.5.12 X X Humidity 3.5.15 4.5.13 X X Drop 3.5.16 4.5.14 X X Pressure equalization 3.5.17 4.5.15 X X Explosive decompression 3.5.18 4.5.16 X X Salt fog 3.5.19 4.5.17 X X Group III Vibration 3.5.20 4.5.18 X X Bounce 3.5.21 4.5.19 X X Altitude 3.5.22 4.5.20 X X Moisture barrier seal 3.5.23 4.5.21 N/A N/A Immersion 3.5.24 4.5.22 N/A N/A Group IV Fungus 3.5.25 4.5.23 X Group V Gun blast 3.5.26 4.5.24 N/A Microphone leakage 3.5.27 4.5.25 X

CONCLUDING MATERIAL )