2.9.5
Electromagnetic SA Test
Perform this test on each size, and type shielded door after performing the
following test: swinging door static load, swinging door sag, door closure
and handle pull tests. Door shall not be acceptable when this test causes
in the reduction of SA by 5 dB. Test HEMP shielded door for SA in the
factory or independent lab prior to shipping to jobsite. HEMP shielded
door shall comply with minimum requirements of MIL-STD-188-125.
Measurements for SA shall be made at [6] [_____] number of test points
required by MIL-STD-188-125 for HEMP single leaf personnel shielded door,
[9] [_____] test points for HEMP double leaf shielded door, and all
penetrations of door. Number of test points shall be scaled up
proportionately for larger doors. Test points shall be located around
periphery of door and at center of astragal. Testing shall be performed in
accordance with MIL-STD-188-125 and modified (orient magnetic loop antenna
co-axial or co-planar or cross which ever gives least SA or maximum signal
pick-up) MIL-STD-285. Required SA shall be 20 dB above minimum of
MIL-STD-188-125 at each test frequency for each test point. Repair is
allowed, however, modification is prohibited.
2.9.5.1
Test Frequencies (Factory Test)
Magnetic field, electric field, and plane wave measurements shall be made
at the following seven test frequencies.
a.
Magnetic field (low impedance): One frequency at 14 KHz, one
frequency at 100 KHz, one frequency at 1 MHz, and one frequency at
10 MHz.
b.
Electric field (high impedance):
One frequency at 30 MHz.
c.
Plane wave (377 ohm): One frequency at 100 MHz, one frequency at
400 MHz, one frequency at 750 MHz, and one frequency at 1 GHz.
2.9.5.2
Test Methodology
Regardless of test methodology or procedure used, orient antenna for
maximum signal pickup or least SA. Orient magnetic loop antennas for
co-axial, co-planar, or cross for maximum signal pick up or least SA.
Orient horn antenna vertically or horizontally for maximum signal pick up
or least SA.
2.9.5.3
Test Instruments and Equipment
a.
Instruments and equipment used shall have current, non-expired
calibration tags. Traceable to the National Institute of
Standards and Technology (NIST).
b.
Spectrum analyzer used shall be of direct reading, digital type.
Use slow sweep, and sweep at least three times prior to taking
measurements.
c.
Signal generator used shall be frequency synthesized.
d.
Dynamic range shall be a minimum of 10 dB above the SA requirement.
SECTION 13095N
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