0.025" Ultra Low Loss Semi-Rigid Coax Cable for Phase Sensitive Microwave Applications

The SR-025-ULL represents a significant departure from conventional semi-rigid coax cable designs, engineered specifically for applications where every 0.1 dB of insertion loss impacts system performance. This 0.025 inch (0.64mm) ultra low loss semi-rigid coaxial cable utilizes an optimized copper tube outer conductor and low density PTFE dielectric that reduces attenuation by approximately 15-20% compared to standard 0.024" constructions across the 10-60 GHz range. Microwave system architects working on satellite downlinks, millimeter wave communication links, and high frequency test benches specify this cable when they need to minimize signal degradation over longer cable runs without moving to larger, less flexible diameters. The silver-plated copper-clad steel center conductor maintains structural integrity during forming while providing the conductivity required for low loss performance up to 60 GHz. Available with custom lengths, SMA, 2.4mm, and 1.85mm connector options, and pre-formed shapes to your mechanical specifications, backed by a 10 meter minimum order quantity.

• Ultra low loss design – optimized copper tube geometry and low density PTFE dielectric reduce attenuation by 15-20% versus standard 0.024" semi rigid cables across 10-60 GHz

• 0.025 inch (0.64mm) diameter – compact form factor that fits the same connector tooling as 0.024" cables while delivering improved electrical performance

• 180 GHz frequency capability – engineered for millimeter wave applications including Ka-band, V-band, and 5G NR frequency ranges up to 180 GHz

• Phase stable copper tube construction – seamless outer conductor ensures consistent phase performance under mechanical stress and temperature variation

• Enhanced conductivity center conductor – silver-plated copper-clad steel with optimized plating thickness for minimum skin effect losses at high frequencies

• Superior shielding effectiveness – solid copper tube provides 100% RF isolation with no signal leakage, critical for sensitive receiver applications

• 0.063 inch minimum bend radius – formable for custom routing while maintaining the ultra low loss characteristics

• PCB solder compatible – rigid construction maintains position after soldering for permanent millimeter wave module integration

• Custom lengths – cut to exact specifications for prototype and production quantities

• Connector options – bare ends, SMA, 2.4mm, 1.85mm pigtails, or fully connectorized assemblies

• 10 meter minimum order – low MOQ for R&D teams and small production runs

• Satellite payload engineers designing Ka-band downlink modules discovered that replacing standard 0.024" jumper cables with SR-025-ULL recovered 0.8 dB of link margin in the receiver chain, allowing smaller antennas or higher data rates

• Millimeter wave radar developers working on 77GHz automotive radar prototypes use this microwave cable for test fixtures because its lower loss enables longer cable runs between the radar head and evaluation boards without signal degradation

• Defense contractors building electronic warfare systems for airborne platforms specify SR-025-ULL for internal RF distribution when every decibel of loss affects jamming effectiveness against modern threats

• Test equipment manufacturers designing next generation vector network analyzers incorporate this semi-rigid coax cable into calibration kits because its phase stability across temperature ensures accurate de-embedding of fixtures

• Research institutions conducting atmospheric propagation studies at 60 GHz use multiple SR-025-ULL hardline cables in their antenna range to feed tightly spaced arrays while minimizing loss-induced measurement uncertainty

• 5G base station developers testing massive MIMO antenna arrays found that standard cables introduced unacceptable loss variations between ports, leading them to switch to SR-025-ULL for consistent channel-to-channel performance

• Space qualification laboratories subjecting this semi-rigid coax cable to thermal vacuum cycling confirm its phase stability meets requirements for geostationary satellite applications where replacement is impossible

• Medical device engineers designing high resolution microwave imaging systems choose semi-rigid cable for its combination of low loss and small diameter, allowing multiple channels to fit through access ports on imaging heads

• Quantum computing researchers building dilution refrigerator test setups appreciate the reduced thermal conductivity of the optimized copper construction, minimizing heat leak into cold stages

• Aerospace test ranges use pre-formed SR-025-ULL assemblies in missile telemetry systems where loss budgets are calculated with zero margin and every 0.1 dB matters

Q: What makes SR-025-ULL different from standard 0.024" semi-rigid cables?

A: The SR-025-ULL features an optimized copper tube geometry and ultra low density PTFE dielectric specifically engineered to reduce attenuation by 15-20% across the 10-60 GHz range. While it uses the same connector tooling as 0.024" cables, the internal construction achieves lower loss through improved conductor surface finish and dielectric purity. This translates to 0.8-1.2 dB less loss per meter at millimeter wave frequencies compared to standard designs.

Q: What is the maximum frequency for SR-025-ULL?

A: The cable is designed for optimal performance up to 60 GHz, with usable characteristics extending beyond. At 60 GHz, insertion loss is 15.1 dB per meter, approximately 3 dB lower than standard 0.024" constructions. The cutoff frequency for higher order modes is 185 GHz, providing clean propagation throughout the specified range.

Q: How does the velocity of propagation affect phase sensitive applications?

A: With 83% velocity of propagation, the electrical length is approximately 1.20 times the physical length. This consistent factor, combined with the phase-stable copper tube construction, allows engineers to predict electrical delay accurately across temperature. For applications requiring matched phase across multiple channels, we offer phase-matched pairs with ±1° at 40 GHz.

Q: Can I solder SR-025-ULL directly to PCB for permanent connections?

A: Yes. The silver-plated copper-clad steel center conductor accepts soldering using standard techniques. Recommended profile is 260-280°C with dwell time under 3 seconds to protect the advanced PTFE dielectric. The rigid copper tube maintains position after soldering, eliminating need for additional strain relief. For high reliability applications, we recommend our pre-terminated assemblies with strain relief boots.

Q: What connectors are recommended for 60 GHz operation?

A: For full 60 GHz performance, we recommend 1.85mm or 2.4mm connectors. For applications below 40 GHz, SMA connectors provide excellent performance at lower cost. All connectors are installed using precision tooling and 100% tested for VSWR and insertion loss. Custom connector configurations are available.

Q: What is the minimum order quantity for SR-025-ULL?

A: 10 meters minimum order, with custom cut lengths available down to 1 inch increments. This low MOQ supports prototyping and R&D projects where full spools are impractical. Production quantities receive volume pricing and shorter lead times.

Q: Can you provide pre-formed shapes to my mechanical drawing?

A: Yes,we accept OEM & ODM. Send a mechanical drawing, 3D model, or dimensioned sketch with bend radii and locations. We deliver semi-rigid cables formed to ±0.5mm tolerance with continuity testing. Forming can be performed before or after connector installation based on your assembly requirements.

Q: Is SR-025-ULL suitable for space applications?

A: Yes. The construction has been tested for outgassing per ASTM E595 and meets requirements for geostationary orbit applications. Phase stability under thermal cycling has been characterized, with typical phase change of less than 5° at 40 GHz over -55°C to +85°C. Full test data available upon request.

Q: How does temperature affect insertion loss?

A: The ultra low density PTFE dielectric maintains stable dielectric constant across -65°C to +125°C, resulting in minimal insertion loss variation. Typical loss change is less than 3% across the full temperature range, compared to 8-10% for standard PTFE constructions. This predictability matters for applications like satellite payloads experiencing wide thermal swings.

Q: Can I order a sample length for evaluation?

A: With our 10 meter MOQ, you can order small quantity for testing and qualification before scaling to production. Cut lengths are individually packaged with desiccant and heat-sealed ends to prevent moisture ingress during storage. Evaluation samples include insertion loss and VSWR data at your specified frequencies.