0.250" Semi‑Rigid RF Cable 50 Ohm Non‑Magnetic SR‑250C Coax Cable for Defense Systems

Price Negotiable
Price: Negotiable
MOQ: 1 ft
Delivery Time: 7-15 work days
Brand: Bing Wire & Cable
Product Description
Product description

SR‑250C semi‑rigid rf cable is a 0.250", 50‑ohm, non‑magnetic coax cable engineered for very high power and low loss applications over extended distances. Its large outer diameter, solid‑metal construction, and carefully controlled dielectric system minimize attenuation and VSWR, making it ideal for backbone RF feeds, high‑duty transmit paths, and mission‑critical links. By using non‑magnetic metals throughout, SR‑250C maintains a negligible magnetic signature, which is essential in MRI/NMR suites, scientific facilities, and environments with strong or carefully controlled magnetic fields. The cable’s semi‑rigid design supports precise forming, excellent shielding, and stable electrical performance even under thermal cycling and vibration, enabling robust installations in demanding industrial and defense systems.

Key features
  • 0.250" 50‑ohm semi‑rigid rf cable for extremely low attenuation and high continuous‑wave power handling.

  • Non‑magnetic conductors and outer tube for use around strong magnets and magnetically sensitive instrumentation.

  • High‑performance dielectric optimized for low loss, low dispersion, and predictable phase over frequency.

  • Outstanding shielding effectiveness, supporting high isolation and low emissions in dense RF environments.

  • Excellent impedance control along the entire length to maintain low return loss at high frequencies.

  • Rugged, all‑metal construction for fixed installations exposed to shock, vibration, or harsh temperatures.

  • Suitable for precision pre‑forming, with repeatable routing through gantries, racks, and long cable trays.

  • Compatible with heavy‑duty connector interfaces designed for 0.250" semi‑rigid and high‑power terminations.

Specifications
Construction
Item Material Diameter (in) Diameter (mm)
Centre Conductor Silver Plated Copper 0.0641 1.6281
Dielectric Solid PTFE 0.209 5.309
Outer Conductor Copper Tube 0.250 +/- 0.001 6.350 +/- 0.025
Electrical Data
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
Mechanical Data
Min. Bend Radius (mm) 3.175
Weight (kg/100m) 15.58
Environmental Data
Temperature Range (℃) -55~+100
RoHS Compliant
Attenuation and Power
Frequency (GHz) Attenuation (dB/m) Power (Watts cW@20℃)
0.50 0.14 1780.0
1.00 0.21 914.8
5.00 0.57 364.5
10.00 0.89 238.3
18.00 1.31 163.2
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Applications
  • High‑Power Transmit and Feed Networks – Use SR‑250C semi-rigid rf cable in transmitter output lines, combiners, and distribution networks where high RF power, low loss, and reliability are crucial.

  • MRI / NMR Infrastructure Cabling – Ideal for non‑magnetic RF trunks between equipment rooms, magnet rooms, and control consoles, preserving SNR and avoiding magnetic interference.

  • Broadcast and Communication Backbones – Suitable for main RF feeds in broadcast transmitters, high‑capacity repeaters, and fixed communication links that demand low insertion loss.

  • Radar and Electronic Warfare Systems – Deployed in radar feed chains, phased‑array manifolds, and EW equipment where long, high‑power runs must maintain amplitude and phase integrity.

  • Accelerator and Scientific Installations – Excellent for RF supply lines in particle accelerators, fusion projects, and large‑scale research labs with strict magnetic cleanliness requirements.

  • Metrology‑Grade Reference Lines – Used as stable reference paths in calibration labs and power‑standard setups, supporting accurate measurements over long cable lengths.

  • Engineered Pre‑Formed Cable Harnesses – Well‑suited for custom multi‑branch harnesses with defined routing, matched electrical lengths, and repeatable production line assembly.

FAQ
Q: When should I choose SR‑250C instead of smaller semi‑rigid sizes?

A: Select SR‑250C when your design calls for very high power, very low insertion loss, or long cable runs where smaller diameters would introduce too much attenuation or heating. It is particularly beneficial as a trunk or backbone cable feeding multiple downstream nodes.

Q: Is SR‑250C fully non‑magnetic?

A: SR‑250C is constructed using non‑magnetic metal alloys and finishes, making it suitable for applications where ferromagnetic materials would distort fields or be attracted by strong magnets. This makes the semi-rigid rf cable a good fit for MRI, NMR, and specialized scientific equipment.

Q: How does its bendability compare to smaller semi‑rigid types?

A: Due to the larger diameter and thicker wall, SR‑250C semi-rigid rf cable requires a larger minimum bend radius and more substantial forming tools than 0.086" or 0.120" cables. It is best used in planned, relatively gentle routing paths rather than tight, compact layouts.

Q: Can SR‑250C be used for phase‑critical systems?

A: Yes. The low‑loss, stable construction supports excellent phase repeatability, and you can specify matched‑length or phase‑matched assemblies for multi‑channel systems. For highly phase‑sensitive arrays, provide detailed electrical requirements at the design stage.

Q: What should I specify when requesting SR‑250C assemblies?

A: When sending an RFQ, include cable type (SR‑250C), required length or cut list, connector types and genders, target frequency range and maximum power, environmental conditions (temperature, vibration, indoor/outdoor, vacuum if applicable), and any pre‑forming drawings or 3D models. If you require phase matching or special testing, note these as well.

Q: Is SR‑250C suitable for outdoor or semi‑outdoor installations?

A: In many cases, yes, when paired with appropriate connectors, sealing, and mechanical protection. For outdoor routes, consider environmental sealing, strain relief, and mounting hardware to prevent moisture ingress and mechanical damage.

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Have questions about our products or want to discuss a custom order? Our team is ready to help you.

Company Shanghai Bing Wire & Cable Co., Ltd.
Location Room 204,BLDG.6,Lane 4703,Rd.Jiaotong,Putuo District ,Shanghai,China
Contact Person Charles

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