Key Manufacturing Process Features of MIL-SPEC Coaxial Cable Assemblies (QPL, Lot Traceability, 100% Testing, COTS)
Outside of the rigorous military specifications (MIL-Spec) that define the best quality Hi-Rel coaxial cable assemblies, there are several other manufacturing and logistic aspects that also greatly impact the suitability of a cable assembly for a given application. These factors include being listed on qualified databases, lot tracing, testing, commercial availability, and access to cable assemblies in a timely manner. Without these additional features, cable assemblies won’t fully meet MIL-Spec, are likely a reliable fit for most extreme applications
QPL
The Qualified Products List (QPL) system is a methods used by the US Department of Defense to ensure authentic and reliable products are readily available for DoD applications. Several quality and authenticity checks are used to ensure that a product on the QPL meets the MIL-Spec designated for that type of product, in the case of coaxial cable assemblies, that is MIL-DTL-17, MIL-PRF-39012, and others.
Lot Traceability
Lot traceability is a key aspect of MIL-Spec and quality assurance in general. If there are issues with several samples of a lot, if each incoming material/component is carefully tracked, then Lot Traceability enables much faster isolation and correction of sourcing and manufacturing defects. This is especially important, as many coaxial cable assemblies are used in diverse applications and for many years. Hence, if there has been a problem with a specific lot of cable assembly products, and accurate traceability methods have been employed, each other unit of that lot could be inspected and replace prior to failure and the potential costs that could incur.
100% RF Testing
100% RF Testing is required in several MIL-Spec for Hi-Rel cables, along with physical and visual inspections. For MIL-Spec purposes, each coaxial assembly is tested and recorded to confirm specified operation, and to prevent defective units from being deployed. The RF tests specific to cable assemblies include VSWR, insertion loss, and dielectric withstanding voltage. Though there are a variety of methods for testing each parameter, the MIL-Spec documents defining coaxial cable assemblies specify the exact tests necessary. 100% RF Testing also benefits a manufacturer, as it can help identify, diagnose, and correct and issues in the manufacturing process that would impact cable assembly electrical performance.
COTS
A sourcing issue that militaries throughout the world have been facing is how to acquire components that meet military specifications without having to custom order, or operate government run factories. One method is to employ commercial off-the-shelf (COTS) components from manufacturers that produce components commercially. Leveraging COTS allows a military to benefit from the rapid pace of commercial advancement, industrial standards, and often lower cost products that are more readily available than custom ordered units. However, the challenge then arises on how to meet reliability and other key military specifications with commercial manufacturers and technologies.
In-stock and Same Day Shipping
Another key sourcing issue that military technology suppliers face on a regular basis, is timely arrival of coaxial cable assemblies. The traditional quote-based and custom designed coaxial cable assemblies can take manufacturer weeks, or months to deliver a product. In the increasingly common predicament of shrinking contract deadlines, and the need for faster prototyping cycles to be competitive, this drawn-out type of legacy sourcing isn’t viable. Hence, the ability to rapidly source custom MIL-Spec/Hi-Rel cable assemblies can be in small and large volumes is an innovative and possibly game-changing feature.