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

4.6.3 Dielectric withstanding voltage (see 3.8). Filters shall be tested in accordance with method 301 of

MIL-STD-202. The following details and exceptions shall apply:

a. Test voltage: Unless otherwise specified (see 3.1), the test voltage shall be as follows:

(1) DC rated filters: 2.5 x rated voltage.

(2) For filters with ac and dc ratings: 2.5 x rated dc voltage. For filters with ac ratings only: 2.8 x rated

rms voltage.

b. Duration of application of test voltage: 5 seconds minimum, 1 minute maximum.

c. Points of application of the test voltage: The test voltage shall be applied between either terminal and

ground (case).

d. Charging current: 50 mA maximum.

e. The sensitivity of the breakdown test equipment shall be sufficient to indicate breakdown when at least 0.5

milliamperes of leakage current flows through the filter under test.

4.6.4 Capacitance to ground and dissipation factor (see 3.9).

4.6.4.1 Capacitance to ground. Capacitance shall be tested in accordance with method 305 of MIL-STD-202.

The following details and exceptions shall apply:

a. Test frequency: 1 MHz � 100 kHz when the nominal capacitance is 100 pF or less, and 1 kHz � 100 Hz

when the nominal capacitance is greater than 100 pF.

b. Voltage: A root-mean-square potential of 1.0 � 0.2 volt when no polarizing voltage is applied.

(Note: Following a dielectric withstanding voltage or insulation resistance test, the capacitance

measurement may be delayed for a period of up to 24 hours.)

4.6.4.2 Dissipation factor. Unless otherwise specified (see 3.1), the dissipation factor shall be measured with a

capacitance bridge or other suitable method at the frequency and voltage specified in 4.6.4.1. The inherent accuracy

of the measurement shall be � 2 percent of the reading plus 0.1 percent dissipation factor (absolute) unless otherwise

specified. Suitable measurement techniques shall be used to minimize errors due to the connections between the

measuring apparatus and the filter. When testing multi-element filters, the effect of series element impedances on

capacitance and dissipation factor readings must be considered. Typically, when measuring high current devices,

this effect is insignificant. However, in some cases, the following test modifications may be required:

L filters: Orient the filter so that the capacitor faces the test points.

Pi filters: Electrically bridge the two live terminals.

T filters: Electrically bridge the two live terminals. (This will reduce, but not eliminate, the effect.)

4.6.5 Insertion loss (at +25�C) (see 3.10). Filters shall be tested in accordance with MIL-STD-220 or to an

approved equivalent at load and at no-load as specified (see 3.1). With only the 10 dB pads, adapters and fixture in

the circuit, 0 dB reference shall have no more than � 1 dB error and the measurements shall be accurate to within

� 3 dB over the specified frequency to 1 GHz.