MIL-F-18327 Filters; High Pass, Low Pass, Band Pass, Band Suppression, And Dual Functioning, General Specification ForThis specification covers the general requirements for passive frequency-selective networks, such as dual functioning, band suppression, band pass, low pass, and high pass \(or any combination thereof\) electric-wave filters, including those employing electromechanical and piezoelectric elements, for use over the frequency range of 0 to 500 megahertz. Filters covered by this specification are intended for use where operation under various environmental conditions is required. This specification covers filters weighing not more than 50 pounds and requiring root-mean-square test voltage ratings not greater than 5,000 volts.

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18

MIL-F-18327F

3.13 Life (at elevated ambient temperature). When filters are tested as specified in 4.7.10, there shall be no

excessive peeling, flaking, chipping, cracking, crazing, or other impairment of the protective coating, no leakage of

filling material, and no evidence of other physical damage such as cracks, bursting, or bulging of the case. Following

the test, these requirements shall be met:

Dielectric withstanding voltage ----------------------------Shall be as specified in 3.9.

Insulation resistance -----------------------------------------Shall be as specified (see 3.10).

Electrical characteristics ------------------------------------Shall be as specified (see 3.1).

3.14 Temperature rise (when specified, see 3.1). When filters are tested as specified in 4.7.11, the temperature

rise above the specified maximum ambient temperature (see 3.1) shall not exceed the value specified (see 3.1), and

there shall be no excessive peeling, flaking, chipping, cracking, crazing, or other impairment of the protective coating,

no leakage of filling material, and no evidence of other physical damage such as cracks, bursting, or bulging of the

case.

3.15 Vibration. When filters are tested as specified in 4.7.12, there shall be no excessive peeling, flaking,

chipping, cracking, crazing, or other impairment of the protective coating, no leakage of filling material, and no

evidence of other physical damage such as cracks, bursting or bulging of the case. Following the test, these

requirements shall be met:

Dielectric withstanding voltage ----------------------------Shall be as specified in 3.9.

Electrical characteristics ------------------------------------Shall be as specified (see 3.1).

3.16 Shock. When filters are tested as specified in 4.7.13, there shall be no excessive peeling, flaking, chipping,

cracking, crazing, or other impairment of the protective coating, no leakage of filling material, and no evidence of

other physical damage such as cracks, bursting, or bulging of the case. Following the test, these requirements shall

be met:

Dielectric withstanding voltage ----------------------------Shall be as specified in 3.9.

Electrical characteristics ------------------------------------Shall be as specified (see 3.1).

3.17 Thermal shock. When filters are tested as specified in 4.7.14, there shall be no excessive peeling, flaking,

chipping, cracking, crazing, or other impairment of the protective coating, no leakage of filling material, and no

evidence of other physical damage such as cracks, bursting, or bulging of the case, or corrosion affecting the

mechanical or electrical operation. Following the test, these requirements shall be met:

Dielectric withstanding voltage ----------------------------Shall be as specified in 3.9.

Insulation resistance -----------------------------------------Shall be as specified (see 3.10).

3.18 Immersion. When filters are tested as specified in 4.7.15, there shall be no excessive peeling, flaking,

chipping, cracking, crazing, or other impairment of the protective coating, no leakage of filling material, and no

evidence of other physical damage such as cracks, bursting, or bulging of the case, or corrosion affecting the

mechanical or electrical operation. Following the test, these requirements shall be met:

Dielectric withstanding voltage ----------------------------Shall be as specified in 3.9.

Insulation resistance -----------------------------------------Shall be as specified (see 3.10).

3.19 Moisture resistance. When filters are tested as specified in 4.7.16, there shall be no excessive peeling,

flaking, chipping, cracking, crazing, or other impairment of the protective coating, no leakage of filling material, and no

evidence of other physical damage such as cracks, bursting, or bulging of the case, or corrosion affecting the

mechanical or electrical operation. Following the test, these requirements shall be met:

Dielectric withstanding voltage ----------------------------Shall be as specified in 3.9.

Insulation resistance -----------------------------------------Shall be as specified (see 3.10).

3.20 Salt atmosphere (when specified, see 3.1). When filters are tested as specified in 4.7.17, there shall be no

evidence of degradation of the coating material, leakage of the potting or filling material, corrosion of metallic parts,

legibility of marking, or other physical damage.