electromagnetic interference. Filters furnished to the requirements of this specification contain shunting ceramic discoidal capacitors and series inductors \(FSC 5915\). Capacitors furnished to the requirements of this specification contain shunting ceramic discoidal capacitors \(FSC 5910\). For the purposes of this specification, feed-through capacitor types \(C circuit configuration\) are referred to herein as a filter. Passband power may be alternating current \(ac\) or direct current \(dc\) and the filters used primarily in the reduction of broadband radio frequency interference. This specification provides for two levels of product assurance requirements. Filters covered by this specification are capable of operation over the temperature range of -55 degrees C to +125 degrees C.

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MIL-PRF-28861D

3.23 Thermal shock and immersion (hermetically sealed filters only). When filters are tested as specified in

4.6.18, filters shall meet the following requirements after the test:

Visual inspection: There shall be no evidence of breakdown, flashover, or other physical damage. In addition,

there shall be no more than 10 percent corrosion of the terminal hardware or mounting surface and marking

shall remain legible.

Dielectric withstanding voltage: As specified in 3.8.

Insulation resistance (+25�C): Shall meet initial requirements (see 3.1).

Insertion loss: Shall meet initial requirements (see 3.1).

3.24 Resistance to soldering heat. When filters are tested as specified in 4.6.19, there shall be no evidence of

internal or external damage. After the test, filters shall meet the following requirements:

Insertion loss (+25�C): Shall meet initial requirements (see 3.1).

Insulation resistance (+25�C): Shall meet initial requirements (see 3.1).

3.25 Salt atmosphere (corrosion). When filters are tested as specified in 4.6.20, there shall be no harmful or

extensive corrosion and at least 90 percent of any exposed metallic surfaces of the filter shall be protected by the

finish. For class S filters, minor cosmetic defects and salt atmosphere damage in the thread area (which is

attributable to the torquing of parts during thermal shock and voltage conditioning) is acceptable. In addition, the

marking shall remain legible.

3.26 Destructive physical analysis (DPA) (class S filters only). When filters are inspected as specified in 4.6.21,

the filters shall meet the requirements of appendix B herein.

3.27 Shock (specified pulse). When filters are tested as specified in 4.6.22, there shall be no evidence of

intermittent open or short-circuiting, and no physical damage to the filter. After the test, filters shall meet the following

requirement:

Insertion loss (+25�C): Shall meet initial requirements (see 3.1).

3.28 Terminal strength. When filters are tested as specified in 4.6.23, no part of the terminals shall loosen or

rupture and no other damage shall result.

3.29 Moisture resistance (hermetically sealed filters only). When filters are tested as specified in 4.6.24, filters

shall meet the following requirements:

Visual inspection: There shall be no evidence of breakdown, flashover, or other physical damage. In addition,

there shall be no more than 10 percent corrosion of the terminal hardware or mounting surface, and marking

shall remain legible after the test.

Dielectric withstanding voltage: As specified in 3.8.

Insulation resistance (+25�C): Shall meet initial requirements (see 3.1).

Capacitance: Shall meet initial requirements (see 3.1).

Dissipation factor: Shall meet initial requirements (see 3.1).

Insertion loss: Shall meet initial requirements (see 3.1).