0.250" Silver Plated Semi‑Rigid Coaxial Cable SR‑250C-SP 50 Ohm Non‑Magnetic Cable
SR-250C-SP stands apart as a high-capacity 0.250" (6.35mm) 50-ohm semi-rigid coaxial cable specifically engineered for long-haul, high-power RF transmission lines in non-magnetic environments, featuring silver-plated copper outer conductor that delivers exceptional skin effect performance with ultra-low attenuation (0.57 dB/m @ 5 GHz) and 653.3W CW power handling at 1 GHz for mission-critical backbone infrastructure. Unlike smaller 0.141" non-magnetic cables optimized for moderate runs or compact modules, SR-250C-SP targets primary RF trunks spanning equipment rooms, transmitter halls, and antenna vaults where maximum power throughput and minimum loss over 50+ foot distances determine system efficiency. The non-magnetic construction ensures zero interference with MRI magnets, particle accelerators, or precision scientific fields, while precision ±0.5Ω impedance control, PTFE dielectric (70% VOP), and 16.8kV RMS voltage rating support demanding broadcast, radar transmitter output stages, and industrial RF processing applications through 19 GHz continuous operation.
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Non-magnetic silver-plated copper shield – Optimized for long-run backbone applications in magnetic fields
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0.250" high-capacity geometry – 653.3W CW @ 1 GHz, 260.0W CW @ 5 GHz power handling
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Ultra-low attenuation – 0.57 dB/m @ 5 GHz, 0.89 dB/m @ 10 GHz for 15+ meter runs
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50-ohm ±0.5Ω precision – VSWR <1.15:1 DC-6.5 GHz, phase stable for reference lines
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3.175mm minimum bend radius – 0.125" radius for planned infrastructure routing
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16.8kV RMS voltage rating – High-power transmit chain and broadcast applications
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PTFE dielectric – Extreme environment reliability, -55°C to +100°C operating temperature
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Custom OEM assemblies – Low MOQ pre-formed backbone cables from engineering drawings
| Item | Material | Diameter (in) | Diameter (mm) |
|---|---|---|---|
| Centre Conductor | Silver Plated Copper | 0.0641 | 1.6281 |
| Dielectric | Solid PTFE | 0.209 | 5.309 |
| Outer Conductor | Silver Plated Copper Tube | 0.250 +0.002/- 0.001 | 6.350 +0.051/- 0.025 |
| Capacitance (pF/m) | 95.2 |
|---|---|
| Impedance (Ohms) | 50 +/- 0.5 |
| Velocity of Propagation (%) | 70.0 |
| Max. Frequency (GHz) | 19 |
| Max. Voltage @60Hz (V RMS) | 16800 |
| Min. Bend Radius (mm) | 3.175 |
|---|---|
| Weight (kg/100m) | 15.58 |
| Temperature Range (℃) | -55~+100 |
|---|---|
| RoHS | Compliant |
| Frequency (GHz) | Attenuation (dB/m) | Power (Watts cW@20℃) |
|---|---|---|
| 0.50 | 0.14 | 951.8 |
| 1.00 | 0.21 | 653.3 |
| 5.00 | 0.57 | 260.0 |
| 10.00 | 0.89 | 169.8 |
| 18.00 | 1.31 | 116.3 |
| 26.5 | ---- | ---- |
| 40.00 | ---- | ---- |
| 50.00 | ---- | ---- |
| 65.00 | ---- | ---- |
| 90.00 | ---- | ---- |
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MRI infrastructure trunks – Primary RF cabling between transmitter rooms and magnet vaults
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High-power broadcast – Main feeder lines from kW-class transmitters to antennas
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Radar transmit chains – High-power output from magnetrons/TPAs to circulators
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Particle accelerator RF – Long distribution lines to klystrons and cavity systems
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Industrial RF plants – 50kW+ plasma systems, materials processing backbone
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Test range cabling – Permanent high-power reference lines, dummy load feeds
Q: How does SR-250C-SP differ from smaller semi-rigid coaxial cables like 0.141C-SP?
A: SR-250C-SP is designed for 15+ meter backbone runs with 653.3W power handling and 0.21 dB/m loss at 1 GHz, while 0.141C-SP serves shorter module interconnects (<20 ft) with higher attenuation and lower power capacity.
Q: What makes this semi-rigid coaxial cable ideal for high-power transmitter output stages?
A: 16.8kV voltage rating, 653.3W CW handling, ultra-low 0.21 dB/m loss at 1 GHz, and ±0.5Ω impedance control ensure maximum power transfer from kW-class amplifiers to antennas or loads without thermal runaway or reflections.
Q: Can SR-250C-SP be field-formed or requires factory pre-forming?
A: Factory pre-forming recommended due to 0.125" minimum bend radius and infrastructure-scale dimensions. We manufacture from your infrastructure CAD files with precise routing for equipment racks, cable trays, and vault penetrations.
Q: What's the magnetic performance verification process?
A: Non-magnetic certification includes <0.1% attraction testing in 3T fields. Material analysis confirms no ferromagnetic alloys (NiFe, steel) in conductor, shield, or support structures.
Q: What production capabilities support large-scale deployments?
A: Low MOQ prototyping (5 pcs) through high-volume OEM production. 50+ assemblies: 3-4 weeks. Annual supply agreements with dedicated capacity for broadcast/radar infrastructure programs.
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