Coaxial cables—often called “coax cables”—may seem like a relic of the past in today’s fiber and IP-dominated world. But in reality, they remain a foundational part of RF communication, television distribution, surveillance systems, and more. Whether you’re an installer, system integrator, or sourcing manager, understanding what a coaxial cable is—and when to use it—can make a huge difference in your project’s performance and cost.
Why Coaxial Cables Still Matter
The Ubiquity of Coax in AV and RF Systems
You’ll find coaxial cables in a wide range of systems:
- CATV and satellite TV installations
- CCTV video surveillance systems
- RF antenna setups
- Legacy data infrastructure (DOCSIS, MoCA)
- Professional audio/video and broadcast studios
Despite the rise of fiber optics and Ethernet, coax cables continue to deliver reliable signal transmission over medium distances, especially where analog or RF components are involved.
Who Needs to Understand Coax?
This guide is especially useful for:
- Electrical or AV system installers
- Industrial procurement officers
- RF engineers and technicians
- Technical buyers comparing cable types
If you’re wondering whether coax fits your next project—or how to choose the right one—read on.
What Exactly Is a Coaxial Cable?
Definition and Core Purpose
A coaxial cable is a type of transmission line designed to carry high-frequency electrical signals with minimal interference. The name “coaxial” comes from the fact that the central conductor and shielding share a common axis.
These cables are used for:
- Analog and digital signals
- High-frequency RF signals
- Video and data transmission
Internal Structure Breakdown
Coax cables are built with four concentric layers:
- Inner Conductor – Copper or copper-clad steel, carries the signal
- Dielectric Insulator – Separates the conductor and shield
- Shielding – Braid/foil that blocks EMI and serves as a return path
- Outer Jacket – PVC or PE, provides physical protection
This layered structure enables coaxial cables to maintain signal integrity even in electrically noisy environments.
Common Types of Coaxial Cables and Their Differences
Here’s a quick comparison of widely used coaxial cable types:
| Cable Type | Impedance | Typical Use |
|---|---|---|
| RG6 | 75Ω | HDTV, satellite, CATV |
| RG59 | 75Ω | Analog CCTV, short-distance video |
| RG58 | 50Ω | RF, antennas, radio systems |
| RG11 | 75Ω | Long-run broadband trunk lines |
50 Ohm vs 75 Ohm – What’s the Difference?
- 50Ω cables are used in RF transmission, two-way radios, antennas, and test systems
- 75Ω cables are typically for TV, video, and broadband
- Mixing the two can result in signal reflection, poor matching, and loss
Where Are Coaxial Cables Used Today?
Key Application Areas
Coaxial cables are still crucial in:
- TV distribution: Cable TV (CATV) and satellite systems
- Security systems: Analog and HD-over-coax CCTV installations
- Internet over coax: DOCSIS modems for broadband access
- RF communication: Antenna feedlines for radios, base stations
- AV extension: HDMI over coax setups for long-distance video
- Military & aerospace: High-reliability signal transmission
Indoor vs Outdoor – Installation Environment Matters
When selecting coax cables, consider these factors:
- Indoor installations: Prefer flexible PVC jackets and flame-retardant ratings
- Outdoor use: Go for UV-resistant PE jackets, waterproof sealing, and direct burial-rated cables
- Shielding: Quad-shield or double-shield for environments with high EMI
How Does Coax Compare with Other Cable Types?
| Feature | Coaxial Cable | Ethernet (Cat6) | Fiber Optic |
|---|---|---|---|
| Signal Type | Analog/Digital | Digital | Optical Digital |
| Distance Capacity | Moderate | Short to Medium | Long |
| EMI Resistance | High | Medium | Very High |
| Installation Cost | Low–Medium | Medium | High |
| Use Case Examples | TV, CCTV, RF | IP cams, LAN | ISP backbone, FTTH |
Can I Replace Coax with Ethernet or Fiber?
It depends. If you’re transmitting video for IP cameras, Ethernet is the better fit. But for analog CCTV, satellite feeds, or RF antennas, coax is still the standard. Many facilities now use hybrid cabling, combining coax and Ethernet for best results.
Choosing the Right Coaxial Cable for Your Project
Key Selection Factors
When selecting coaxial cables, evaluate:
- Impedance (50Ω or 75Ω) based on your system type
- Frequency range – Higher frequencies need lower loss cables
- Shielding – More shielding = better EMI protection
- Environment – Indoor, outdoor, burial, or plenum-rated
- Connectors – Make sure cable type matches BNC, F-type, SMA, or N-type connectors
Project Scenarios and Recommended Models
| Application | Recommended Cable |
|---|---|
| Analog CCTV | RG59 (75Ω) |
| HDTV or satellite TV | RG6 (75Ω) |
| Antenna feedlines | RG58 or LMR400 (50Ω) |
| Long cable runs (ISP) | RG11 (75Ω) |
Self Check: Is Coax Right for My Application?
Answer the following questions:
- Is your system analog (TV, RF, CCTV)? → Coax is likely your best option
- Are you dealing with long runs where EMI is a concern? → Use RG6 or RG11
- Need high bandwidth or internet connectivity? → Consider Ethernet or coax + DOCSIS
FAQs – Understanding and Using Coaxial Cables
Q1: Is coaxial cable analog or digital?
Coax can carry both analog and digital signals depending on the equipment and modulation used.
Q2: Can coax carry internet data?
Yes, through DOCSIS cable modems or MoCA adapters, coax can provide high-speed internet.
Q3: What’s the maximum length for a coaxial cable?
Depends on the type. RG6 is ideal up to 150ft for TV. Beyond that, RG11 or amplifiers may be required.
Q4: How do I identify a cable type?
Check the printed markings on the cable jacket (e.g., “RG6 75Ω”).
Q5: Can I cut and rejoin coaxial cables?
Yes, but use proper connectors and crimp tools to avoid signal loss or interference.
Welcome Your Inquiry
Need high-performance coaxial cables for your next project?
Bafitop provides RG6, RG59, RG58, and RG11 coax cables with international shipping, testing reports, and custom labeling options. Whether you’re building a satellite distribution system, CCTV network, or RF communication link, we’re here to support your success.
📩 Email: sales@bafitop.com
📞 Phone: 86-15817341810
Request free samples, datasheets, or expert consultation today.
