RG-214 Double-Shielded Coaxial Cable: Specs and Uses

Engineers and RF signal technicians frequently require high-performance transmission lines capable of operating under strict signal isolation demands. The RG-214 double shielded coaxial cable remains a standardized choice across military communications, broadcasting, and high-frequency industrial test benches. Built in compliance with international standards such as MIL-C-17 (specifically MIL-C-17/75) and IEC 60096, this cable provides exceptional shielding effectiveness and physical durability.

This technical guide reviews key RG-214 cable specs, material layout, comparative differences such as RG-214 vs RG-8, and core installation guidelines. As part of Worldpeak's technical knowledge base, this article delivers practical engineering insights for selecting a reliable 50 ohm RF coaxial cable solution.

Cable Construction and Physical Specifications

The physical construction of the RG-214 double shielded coaxial cable directly dictates its electrical behavior and environmental resistance. Unlike basic single-braid cables, the RG-214 architecture focuses on dual-layer shielding and silver-plated conductors to minimize resistive losses at high frequencies.

Material Layer Breakdown

• Center Conductor: Stranded Silver-Plated Copper (7 x 0.75 mm / 7 x 0.0296 in)
• Dielectric Core: Solid Polyethylene (PE)
• Primary Shield: Silver-Plated Copper Braid
• Secondary Shield: Silver-Plated Copper Braid
• Outer Protective Jacket: Non-Contaminating Polyvinyl Chloride (Type IIA PVC)

Key Material Functions

• Center Conductor: Composed of seven strands of silver-plated copper wire with an overall nominal diameter of 2.25 mm. The silver plating leverages the skin effect at higher frequencies, reducing RF attenuation compared to bare copper strands.
• Dielectric Layer: Solid polyethylene (PE) insulation maintains a consistent dielectric constant, ensuring stable characteristic impedance along the line.
• Double Braided Shielding: Two consecutive layers of woven silver-plated copper wire provide high optical coverage. This dual-layer structure significantly reduces RF leakage and protects sensitive receiver equipment from external electromagnetic interference (EMI).
• Outer Protective Jacket: A robust non-contaminating PVC outer sheath resists UV degradation, moisture ingress, and ambient chemical exposure in indoor and outdoor deployments.

Electrical Performance Characteristics

Verifying standard RG-214 cable specs ensures proper matching with transmitters, receivers, filters, and antenna feeds. The primary engineering goal is maintaining precise 50-ohm impedance while keeping reflection loss low across operating frequencies.

Standard Nominal Attenuation Data

Below are typical published attenuation figures per 100 meters at 20 degrees C:

• 10 MHz: Approx. 1.9 dB / 100 m

• 100 MHz: Approx. 6.3 dB / 100 m

• 400 MHz: Approx. 13.8 dB / 100 m

• 1,000 MHz (1 GHz): Approx. 23.8 dB / 100 m

• 3,000 MHz (3 GHz): Approx. 46.5 dB / 100 m

Comparative Analysis: RG-214 vs RG-8

System designers often evaluate RG-214 vs RG-8 when selecting coarse 0.405-inch flexible coax for medium-to-high power RF circuits. While both belong to the standard 50-ohm cable family, their internal engineering differs significantly.

1. Shielding Construction and EMI Rejection

• RG-214 double shielded coaxial cable: Features two layers of silver-plated copper braiding. This dual design provides superior RF isolation, making it suitable for co-located antennas and high-noise radio environments.

• RG-8: Typically utilizes a single bare copper braid. Consequently, it offers less shield coverage and lower noise rejection capability compared to RG-214.

2. Conductor Surface and Long-Term Stability

• Silver plating on the center conductor and shielding braids in the RG-214 cable specs prevents copper oxidation over time, maintaining consistent high-frequency insertion loss over extended service lives.

• Standard bare copper in standard RG-8 can oxidize when exposed to air and moisture over long periods, leading to gradual increases in high-frequency attenuation.

3. Mechanical Flexibility

• The stranded center conductor of RG-214 double shielded coaxial cable provides superior flexibility compared to solid-center RG-8 variants, facilitating installation in tight enclosures or cable trays.

Standard Engineering Applications

Because of its double-shielded construction and high power tolerance, RG-214 double shielded coaxial cable is commonly specified for:

• Military and Aerospace Ground Links: RF connections adhering to strict MIL-C-17 specs for tactical radios and radar equipment.

• Radio Base Stations and Antenna Feeds: Interconnecting jumpers between power amplifiers, duplexers, and antenna systems.

• RF Test and Measurement Systems: Stable interconnect lines used in laboratory environments where low phase variance and reliable shielding are necessary.

• High-Power Broadcast Equipment: Connecting HF, VHF, and UHF transmitters to tuning units where high dielectric voltage ratings are required.

Quality Control and Inspection Standards at Worldpeak

To ensure every production batch of 50 ohm RF coaxial cable fulfills international standards like ISO 9001 and MIL-C-17, standard factory quality controls are applied:

1. Conductor Integrity Checks: Dimensional verification and plating thickness monitoring on all silver-plated copper stock.

2. Dimensional Monitoring: Continuous inline laser micrometer monitoring during dielectric extrusion to maintain consistent impedance control.

3. Shielding Density Verification: Inspection of braid angle and carrier count to maintain high optical coverage on both shield layers.

4. Electrical Testing: Sweep testing with vector network analyzers to verify impedance consistency, return loss, and insertion loss specs across the rated frequency spectrum.

Practical Installation Guidelines

When integrating RG-214 double shielded coaxial cable into RF systems, follow standard mechanical practices:

• Connector Compatibility: Match the cable with standard 0.405-inch clamp or crimp RF connectors (such as N-type, BNC, or UHF connectors) rated for stranded conductors.

• Bend Radius Requirements: Observe recommended minimum bend radii—typically around 50 mm for static installations and 100 mm for dynamic applications—to avoid deforming the polyethylene dielectric.

• Sealing and Moisture Protection: Apply appropriate self-amalgamating tape or weatherproofing boots over outdoor connector interfaces to prevent moisture intrusion into the silver braid layers.

For complete technical specifications or custom assembly configurations, visit Worldpeak's RF coaxial cable lineup to find the right component for your installation needs