- Buyers Guide
Aerospace & Defense Electronics Supplement
Early Returns: U.S. Export Control Reform Positive
A&D Test & Measurement
Efficient Design and Analysis of Airborne Radomes
San-tron Inc. introduces a new series of braze-free, 50 Ω right angle connectors that feature silver-plated center contacts and bodies, and an Albaloy-plated coupling nut. They are designed in accordance with MIL-STD-348 interface and the design allows for the connectors to be used up to 11 GHz, while most other right angle connectors are limited to 9 GHz.
Utilizing Hydromat technology, San-tron has redefined the manufacturing process in the implementation of these right angle type N connectors by harnessing the high performance, low cost and adaptability of this technology. This approach results in:
Lower operating costs
Lower component costs
Broad scope – commonality of components
Highly reproducible RF performance
Indestructible mechanical performance
Figure 1 illustrates how this technique is adaptable to many applications. The base module encompasses the type N interface, the coupling mechanism, the right angle structure and the launch. With the base module used as the foundation of a product line, a host of possibilities for different applications opens up. Through the deployment of secondary modules, as illustrated, the following right angle topologies can be implemented:
Between series adapters
Black box portals
The heart of this methodology is the type N interface base module that incorporates the right angle and launch zones. Machined from solid 1.00-inch bar stock on a 16-head Hydromat, the RF structure, from reference plane through the right angle and into the subsequent launch, is controlled by primary machining processes. Therefore, there are no secondary operations that can shift the centerline development of the RF structure. Every assembly is identical in phase length, impedance structure and registration of the dielectrics and center contact — a direct outcome of the investment in Hydromat technology.
The tooling budget to outfit a Hydromat is a customized deployment that does not support flexible manufacturing. The technique also requires a 40-hour setup and cannot be deployed with an expectation of inventory turns at the component level. When this process is turned on, however, a huge amount of product can be run and important economies of scale can be realized. Therefore, although the economic disadvantage appears obvious (the need to carry a six-month inventory is against every principle of modern management operations), an upside is apparent when the total logistic stream is reviewed. This one complex component supports a wide variety of products with a simplified routing structure.
First implemented as a clamp-style right angle connector, this was a very simple bill-of-material (BOM), thus establishing the most basic logistic stream. Using standard cable termination hardware that has been offered by San-tron for over 50 years, the commonality of components ensured a low cost, high turn inventory structure. A single new component was required to complete this design: a physically short, easy-to-machine body that could be dropped complete from low cost Brown & Sharp operations. This technique resulted in an assembly comprised of one complex, low turn component and a BOM of low cost, high turn inventory, fulfilling the need for lean manufacturing deployment.
The second implementation is a right angle type N adapter, shown in Figure 2, the development of which makes use of three unique technologies. The first one is the implementation of the dual displacement press fit. The primary press fit is composed of opposing smooth bore cylinders that result in an IP-66 junction. The secondary press fit is a traditional straight knurl that enhances mechanical captivation. This dual displacement press fit establishes a mechanical junction that is stronger than either of the individual methods. Under destructive torque-to-failure testing, the connector bodies are grossly deformed without rupture of the press fit junction. The second technology introduces an optical wave shaping through the right angle connector. Employing optic principles, the dielectric and center contact are developed such that the TEM field is pre-shaped and intensified through the interior elliptic surface. As shown in Figure 3, this technique establishes a reflection coefficient (r) through the right angle structure that is limited to ρ = +0.015 (51.5 Ω), and then recovers to ρ = –0.030 (47.1 Ω). Notice also the inductive characteristics of the two interfaces. Due to the geometric plan of the type N plug, the typical inductive spike of the type N interface is virtually eliminated to a level of ρ = +0.022 (52.2 Ω). The type N jack interface is more traditional and results in ρ = +0.039 (54.1 Ω). As an added benefit, the dielectric geometries are such that miter joints and secondary operations were again eliminated from the design, thus further reducing sources of error and cost. The third technology is the development of solder-free compliant pin contacts. The center contact is a two-piece construction comprised of a cross-drilled tab contact machined of brass and a slotted compliant pin machined of BeCu. These two components are interlocked and establish an irreversible connection. The resultant contact exhibits a highly reproducible RF structure devoid of operator skill and process variations. This development of the right angle cable plug and the right angle adapter establishes the basis for new products offering advanced technological enhancements. The omission of brazing and soldering operations establishes a seamless technology that is easily implemented throughout San-tron’s worldwide organization. The process is highly constrained and reproducible. The omission of brazing and soldering not only eliminates the variations associated with reduction atmospheric ovens and soldering process, but also supports the lean manufacturing goals of reducing lead-times, eliminating the use of special processes, and reducing the criticality of employee training and certification. Whether these assemblies are to be manufactured in the Caribbean, Suzhou, China, or at San-tron headquarters in Ipswich, MA, the resultant connectors exhibit advanced performance characteristics at a commercial pricing structure.
Get access to premium content and e-newsletters by registering on the web site. You can also subscribe to Microwave Journal magazine.