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

f. The manufacturer shall maintain records on each lot date code. The manufacturer shall record when in-

process controls and groups A and B inspections start and when they have been completed.

g. Maximum lot size for broadband type filters shall be 500 pieces.

h. Maximum lot size for high-frequency filters (3 dB cut-off frequency (fc) > 500 kHz) shall be 2,000 pieces.

4.5.5 Group A inspection.

4.5.5.1 Class B filters. Filters shall be subjected to the tests in table VI in the order shown, for class B devices.

Subgroup 1 tests shall be performed on 100 percent of the product supplied under this specification to the extent

specified. Filters failing the tests of subgroup 1 shall be removed from the lot. Lots having more than 10 percent total

rejects shall not be furnished on the contract or purchase order. Failures from radiographic inspection shall be

removed from the lot and shall not be counted as rejects. Failures from the seal test shall not be counted toward the

total rejects. However, if the number of seal test failures exceeds 10 percent, the lot shall be rejected. If the number

of seal test failures does not exceed 10 percent, then these failures may be reworked and retested to the subgroup 1

tests. For subgroup 2, a sample of parts from each inspection lot shall be randomly selected in accordance with

table VII. There shall be no failures allowed. For subgroup 3, five samples shall be selected at random from each

inspection lot. Test samples for the solderability test may be selected from subgroup 1 electrical failures. There shall

be no failures allowed.

4.5.5.1.1 Rejected lots (subgroup 2). If an inspection lot is rejected, the contractor may rework the lot to correct

the defects or screen out the defective units, and resubmit the lot for inspection. Samples shall be randomly selected

in accordance with table VII. If one or more defects are found, the lot shall be rejected and shall not be supplied to

this specification.

4.5.5.1.2 Rejected lots (subgroup 3). If an inspection lot is rejected, the contractor may use one of the following

options to rework the lot:

a. Each production lot that was used to form the failed inspection lot shall be individually submitted to the

solderability test. Production lots that pass the solderability test are available for shipment. Production lots

failing the solderability test can be reworked if submitted to the solder dip procedure in b.

b. The manufacturer submits the failed lot to 100 percent solder dip using an approved process in accordance

with 3.5.4. Following the solder dip, the electrical measurements required in group A, subgroup 1 tests

shall be repeated on 100 percent of the lot (seal test shall also be performed on hermetically sealed filters).

The PDA shall be as for the subgroup 1 tests. Five additional samples shall then be selected and

subjected to the solderability test with no failures allowed. If the lot fails this solderability test, the lot may

be reworked a second time and shall be retested. If the lot fails the solderability test after the second

rework, the lot shall be rejected and shall not be furnished against the requirements of this specification.

4.5.5.1.2.1 Disposition of samples. The solderability test is considered a destructive test and samples submitted

to the solderability test shall not be supplied on the contract.

4.5.5.2 Class S filters. Filters shall be subjected to the tests specified in table VI, in the order shown, for class S

devices. Subgroup 1 tests shall be performed on 100 percent of the product supplied under this specification. For

the thermal shock, voltage conditioning, insulation resistance and dielectric withstanding tests the PDA for each test

shall be 2 percent maximum (Note: During the last 50 hours of the voltage conditioning test the percent defective

allowed shall be 0.2 percent maximum or one unit, see 4.6.2.2.2e). For the capacitance, voltage drop, and insertion

loss tests the PDA shall be 3 percent maximum. Lots having more than 10 percent total rejects shall not be furnished

on contracts. Failures from the radiographic inspection and fine leak seal test shall be removed from the lot and shall

not be counted as rejects. Failures from the gross leak seal test shall not be counted toward the total rejects.

However, if the number of gross leak seal test failures exceeds 10 percent, the lot shall be rejected. If the number of

gross leak seal test failures does not exceed 10 percent, then these failures may be reworked and retested to the

subgroup 1 tests. For subgroup 2, a sample of parts from each inspection lot shall be randomly selected in

accordance with table VII. There shall be no failures allowed. For subgroup 3, five samples shall be selected at

random from each inspection lot. Test samples for the solderability test may be selected from subgroup 1 electrical

failures. There shall be no failures allowed.