Semi rigid coaxial cables are essential in high frequency – applications up to 110 GHz. What sets them apart is their unique mechanical behavior: they can be bent into their final shape—by hand or machine—and retain that shape permanently. This makes them ideal for RF environments requiring precise routing and repeatable geometry.
Our semi-rigid cables are sourced from certified suppliers qualified under MIL-DTL-17 and listed on the US Defense Logistics Agency’s Qualified Products List (QPL).

Key Takeaways:

• Operating up to 110 GHz, semi-rigid cables offer superior shielding (100%) and low VSWR.
• Available in diameters from 0.020″ to 0.500″ and impedances from 10 to 100 ohms.
• Low-loss variants reduce attenuation by 20% and support temperatures up to 250 °C.
• Stainless steel versions are ideal for cryogenic and medical applications due to low thermal conductivity.
• Dielectric and conductor materials (e.g., PTFE, silver-plated copper) directly impact attenuation, phase, and power stability.

“For critical RF assemblies, semi-rigid cables provide unmatched performance and mechanical integrity—especially when pre-conditioned and properly bent.”

– Stefan Burger, RF Expert

Proper usage involves precision cutting, careful stripping, and ideally pre-conditioning—a thermal cycling process that stabilizes the dielectric and prevents VSWR drift caused by stress relaxation. Bending requires specialized fixtures that avoid pinching or deforming the cable’s structure.

Assemblies should follow tight mechanical and electrical standards:

• Maintain correct bend radius.
• Avoid micro-cracks or burrs at the shield edge.
• Prevent dielectric damage during jacket removal.
• Always account for material spring-back after bending.

Whether you’re prototyping or preparing for mass production, semi-rigid cables require careful planning and tooling to preserve performance. Our full lineup includes low-loss and stainless steel variants, as well as custom solutions based on QPL-certified part numbers.
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