MIL-DTL-18239E(AS)
3.4.5 Insulation resistance. The insulation between the winding and the core, and between
the case and terminal shall withstand 500 volts rms 60-cycle ac without breakdown when tested in
accordance with 4.7.7. The insulation resistance shall exceed 1 megohm between the indicate
points following the application of this voltage.
3.4.6 Distortion. The rms harmonic distortion in the acoustic output of the earphone shall
not exceed 2.5 percent at any fundamental frequency between 200 and 7,000 Hz, when tested in
accordance with 4.7.8.
3.4.7 Overload. The design of the earphone unit shall be such that the unit shall show no
structural failure or defect and only minor changes in frequency response characteristics as a result
of the overload test (see 4.7.9).
3.5 Environmental.
3.5.1 Humidity. The sound pressure versus frequency characteristics of the earphone unit
shall not vary more than 6 db from normal seal level performance at any frequency between
100 and 7,000 Hz when tested in accordance with the humidity test of 4.7.10.
3.5.2 Moisture. The sound pressure versus frequency characteristics of the earphone unit
shall not vary more than 3 db from normal sea level performance at any frequency between
100 and 7,000 Hz following exposure to the moisture resistance test (see 4.7.11).
3.5.3 Salt spray. The sound pressure versus frequency characteristics of the earphone unit
shall not vary more than 3 db from normal sea level performance at any frequency between
100 and 7,000 Hz after drying following exposure to the salt spray test (see 4.7.12).
3.5.4 Impact. The sound pressure versus frequency characteristics of the earphone unit shall
not vary more than 3 db from normal sea level performance at any frequency between 100 and
7,000 Hz and no structural failure shall be evidenced after 12 drops at random (see 4.7.13).
3.5.5 Electromagnetic interference. The electromagnetic interference of the earphone shall
cause no more than a 5 degree deflection of a magnetic compass when tested in accordance with
4.7.14.
3.5.6 Aging. The earphone unit shall be such that the unit will show no structural failure or
defect and only minor changes (less than 1 db) in frequency response characteristics as a result of
the aging test (see 4.7.15).
3.6 Nomenclature and nameplates. Nomenclature assignment and nameplate approval for
approval equipment identification shall be in accordance with MIL-N-18307.
7
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business