MIL-DTL-38449D
4.4.3 Functional test. The tests of Table III shall be performed when required during
qualification testing as specified and at the conclusion of the tests of 4.4.6.1, 4.4.7.1, 4.4.7.2,
4.4.7.8, 4.4.8, 4.4.7.3, 4.4.7.4, 4.4.7.7, 4.4.7.6, and 4.4.7.5. The test shall be conducted using a
test circuit similar to that shown on Figure 4 and as specified in 3.7.1. Instrument accuracy shall
be demonstrated by repeating instrument readouts per test. All tests results shall be recorded.
4.4.4 Ripple test. This test shall be conducted in accordance with the paragraph entitled, Ripple,
and Figure entitled, Frequency Characteristics of Ripple in 28 Volt DC E1ectric System, of MIL-
STD-704. The specified voltage levels and frequencies shall be inductively coupled in series
with the positive power input terminals. The unit shall be functionally tested as specified in 4.4.3
during application of the specified ripple voltages.
4.4.5 Transient sensitivity. Transient sensitivity shall be performed as shown on Figure2(A).
Capacitor C shall be charged to the supply voltage and switched to the amplifier input. The
supply voltage shall be varied, and the minimum peak voltage required to trigger the amplifier
shall be determined. The minimum voltage at each of the following time constants shall be
plotted. Figure 2(B) depicts the minimum allowable voltage the unit shall operate in the "may
operate range" and the "shall operate" range.
a. 3 microseconds (usec)
b. 5 usec
c. 10 usec
d. 100 usec
e. 1,000 usec
f. 15,000 usec
4.4.6 Transient and noise susceptibility tests.
4.4.6.1 Transient test. This test shall be in accordance with the paragraph entitled, Voltage
Transients, and Figure entitled, Transient Surge DC Voltage of Step Function Loci Limits for
Category C Equipment, of MIL-STD-704. A rectangular pulse, 0.04 second in duration, rising
from 24V to 80V dc shall be applied h the input power terminals. The functional test specified in
4.4.3 shall be conducted during application of transients.
4.4.6.2 Noise susceptibility. The unit shall be subjected to a test in accordance with the steps
outlined below and Figure 5, or an equivalent test meeting the requirements set forth in 3.7.5.3:
a. Power supply shall be set for 28V dc.
b. Switch S2 shall be closed, and amplifier shall come ON in READY position, with
DS1 lighted.
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