Raychem Matched-Impedance Splices
Cool Product Report

As one of a dwindling number of people who still read paper print versions of our electronics trade magazines, I find it more convenient to scan for noteworthy new products and articles to report about on RF Cafe. I tear out pages and put them a stack for eventual reference. The April 2016 issue of Microwaves & RF had a feature on a new line of Raychem (TE Connectivity) heat-shrink matched-impedance splices. I have used Raychem's heat-shrink splices for many decades on standard signal and power wire in cases where it was more convenient that soldering the joint, cleaning it, and then sliding a section of heat-shrink tubing over it. The only disadvantage of a Raychem type splice is the cost and it is a little bulkier than the other way.

I cannot ever recall an instance where I spliced a coaxial cable rather than replace the entire length. There have been times when the coax was laced into a harness assembly and replacing it was a real pain in the posterior, especially since it was in the back of a row of equipment racks with no easy access. Having had these new matched-impedance splices from Raychem would have been real nice.

It appears for now the splice kit is only available for RG-393 coaxial cable, which is a 50 Ω, 0.39-inch diameter cable rated to around 6 GHz. The advertised impedance match tolerance is +10%/-3% (VSWR range of 1.03:1 to 1.10:1).

Per TE Connectivity's website:

"TE Connectivity Ltd. (TE) (NYSE: TEL), a world leader in connectivity and sensors, announced its Raychem matched impedance splices for aerospace applications. Designed to comply with MIL-PRF-32517 standard, the splices solve the problem of costly removal and replacement of damaged coaxial cable by allowing fast, easy in situ repairs that maintain characteristic impedance and other electrical properties of the system.

Coaxial cables are used extensively within aerospace and avionics systems, yet there has been no effective solution to repair such cables damaged during operational use. Until now, any affected cables within the airframe had to be disconnected, removed and then replaced, which was both time-consuming and costly.

'Our engineers have developed a solution that addresses this common challenge by matching the characteristic impedance of the cable itself and offering the greater capability of in situ repair,' said Janeann Avants, product manager, Global Aerospace, Defense & Marine, TE Connectivity. 'Our Raychem matched impedance splices reduce the time and effort needed for repairs and lessen the number of cables that need to be replaced.'

TE's new Raychem matched impedance splices are designed for the harsh environments of military and commercial aerospace applications and are well suited for extreme temperatures, high vibration, high EMI and corrosive environments. The splice contains three components: a hexagonal crimp barrel for the center conductors, a dielectric shell that helps maintain cable geometry for impedance control, and a heat-shrinkable SolderShield splice that both terminates the cable's shield and provides sealing to protect the splice environmentally." 

Download the Raychem Matched-Impedance Splices brochure here.

About TE Connectivity

"TE Connectivity (NYSE: TEL) is a $12 billion global technology leader. Our connectivity and sensor solutions are essential in today's increasingly connected world. We collaborate with engineers to transform their concepts into creations – redefining what's possible using intelligent, efficient and high-performing TE products and solutions proven in harsh environments. Our 72,000 people, including over 7,000 engineers, partner with customers in close to 150 countries across a wide range of industries. We believe EVERY CONNECTION COUNTS."

Posted August 19, 2016