MIL-DTL-287J
FIGURE 2. VSWR test using coupled sliding load.
4.7.4.1 For first article inspection. For assemblies that operate up to 12.4 GHz inclusive, the lengths shall be 12
inches (305 mm) and 24 inches (610 mm). For assemblies that operate above 12.4 GHz and through 26.5 GHz, the
lengths shall be 6 inches (152 mm) and 12 inches (305 mm). For assemblies that operate above 26.5 GHz, the
lengths shall be 1 inch (25 mm) and 2-1/4 inches (63 mm).
4.7.4.2 For Group A inspection. The VSWR measurements under group A inspection shall be performed on the
actual length that is being acquired.
4.7.5 Pressurization. The assembly shall be subjected to the internal air pressure in pounds force per square
2
inch gauge (lbf/in ) specified (see 3.1 and 3.5.4), while immersed in water. The longitudinal axis of the assembly
shall be nominally parallel to the surface of the water, and the uppermost portion of the assembly shall not be less
than 6 inches (152 mm) and not more than 12 inches (305 mm) below the surface. The temperature of the water
shall be 20° ± 5° C. Any bubbles coming from within the assembly shall be considered as leakage. Bubbles which
are the result of entrapped air on the exterior parts of the assembly shall not be considered as leaks. The stability of
insertion loss and VSWR shall be measured while under pressure as specified in 4.7.3 and in 4.7.4, respectively.
The unit does not have to be immersed in water during insertion loss and VSWR tests. Any areas of non-adherence
of the jacket (if applicable) should be noted after the assembly has been under the pressure for 5 minutes. Ridges
in the rubber that show under pressure are to be discounted, and, in general, non-adherent areas .125-inch (3.18
mm) square or smaller may be disregarded. In case of doubt, any non-adherent area which does not visibly
increase in size when the assembly is subjected to the applicable pressure for 24 hours will be acceptable.
9
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business