If you’re running TV feeds, broadband internet, or CCTV cameras, coaxial cable specifications are still one of the most reliable ways to consider moving high-frequency signals without turning your wiring closet into a science project.

But here’s the problem: most people treat all coaxial cable as the same “TV cable,” and then wonder why they get fuzzy video, unreliable modems, or noisy CCTV footage.

This guide breaks down the key coaxial cable specifications you actually need to care about:

• Common coax types: RG‑6 vs RG‑59
• Impedance (50 Ω vs 75 Ω)
• Shielding (braid, foil, dual/quad shield)
• Signal loss/attenuation
• Which specs matter for TV, broadband, and CCTV

If you want a broader overview of all cable types (Ethernet, speaker wire, control, etc.), see the main guide:
The Only Cable Specification Guide You’ll Ever Need.

What Is a Coaxial Cable?

A coaxial cable (or “coax”) is a round cable designed to carry high-frequency signals with minimal interference. It’s built like a layered tube:

1. Center conductor – solid copper or copper-clad steel
2. Dielectric insulation – keeps spacing and impedance stable
3. Shielding – usually braided copper plus aluminum foil
4. Outer jacket – PVC or PE for mechanical and environmental protection

This construction keeps the signal “trapped” inside the cable and reduces noise from outside sources like AC power lines, LED drivers, or other RF sources.

Key Coaxial Cable Specifications (What Actually Matters)

When you compare coaxial cable specifications, focus on these four:

1. Impedance (Ω)
2. Cable type (RG-6 vs RG-59 and others)
3. Shielding level and construction
4. Signal loss (attenuation) at your frequency and distance

1. Impedance: 50 Ω vs 75 Ω

Impedance is the cable’s AC resistance to the signal, measured in ohms (Ω). The important bit:

• 75 Ω coax → TV, satellite, cable internet, most CCTV
• 50 Ω coax → Radio, RF transmitters, some wireless/antenna systems

For almost all residential and light commercial low-voltage applications:

If it’s TV, satellite, or broadband: you want 75 Ω coax.

Using the wrong impedance can cause:

• Reflections in the line
• Signal loss
• Poor modem sync or degraded picture quality

2. Coax Types: RG‑6 vs RG‑59

For low-voltage installers, the two most common coax types are RG‑6 and RG‑59. Both are 75 Ω, but they’re not interchangeable.

RG‑6: The Workhorse for TV and Broadband

Best for:

• Cable TV and satellite TV
• Cable broadband internet
• Longer runs where signal loss is a concern

Key characteristics:

• Larger diameter and better dielectric
• Lower signal loss than RG‑59 at TV and internet frequencies
• The standard choice for modern CATV/satellite and modems

In practice, for any new TV, satellite, or broadband installation, RG‑6 is the default choice.

RG‑59: Older CCTV and Short-Run Applications

Best for:

• Short-run analog CCTV (especially older systems)
• Some baseband video applications at short distances
• Specialty uses where a smaller, more flexible cable is needed

Key characteristics:

• Slightly thinner and more flexible
• Higher signal loss than RG‑6 at high frequencies
• Often used in legacy installs and low-bandwidth video over short distances

If you’re running modern HD video over HD-CVI, TVI, or AHD, or you need longer camera runs, RG‑6 or a high-quality RG‑59 with solid copper and good shielding is strongly recommended.

3. Shielding: Controlling Noise and Interference

Shielding prevents outside electrical noise from leaking into your signal and stops your cable from radiating noise into other systems.

Common shielding configurations:

• Single shield – usually a single braid (e.g., 60% coverage)
• Dual shield – foil + braid
• Tri-shield – foil + braid + second foil
• Quad-shield – foil + braid + foil + braid

For real-world installations:

• Standard indoor TV runs: Dual-shield RG‑6 is often enough.
• Noisy environments/commercial/long runs: Quad‑shield RG‑6 is safer.
• CCTV near electrical equipment or lighting: use well‑shielded coax.

When comparing coaxial cable specifications, look for:

• Braid coverage (e.g., 60%, 90%, 95%) – higher coverage = better shielding
• Foil shield presence – especially important at higher frequencies
• Solid copper braid is better than copper-clad aluminum for grounding and low-resistance paths.

4. Signal Loss (Attenuation)

Every coax cable loses some signal over distance. This is called attenuation, usually listed in dB per 100 ft (or per 100 m) at certain frequencies.

The higher the frequency, the more loss you’ll see.

Typical trend:

• At lower frequencies (like analog CCTV video): RG‑59 can be acceptable on short runs.
• At higher frequencies (like satellite, DOCSIS cable internet): RG‑6 is strongly preferred because it has lower loss.

When you check a spec sheet, you’ll see something like:

• RG‑6: 2–3 dB loss per 100 ft at typical CATV frequencies (example values)
• RG‑59: higher dB loss at the same frequency

Rule of thumb:

• For long runs or high-frequency signals, choose the cable with lower dB/100 ft at your operating frequency—usually RG‑6.
• If you’re approaching or exceeding the recommended max distance for a given system, you may need amplifiers or active baluns in addition to better coax.

Coaxial Cable Specs by Application

Let’s match the coaxial cable specification to the job: TV, broadband, and CCTV.

Coax for TV (Cable & Satellite)

Primary goals:

• Strong signal from the service entry to every TV
• Minimal interference or reflections
• Compatibility with splitters, set-top boxes, and tuners

Recommended specs:

• Impedance: 75 Ω
• Type: RG‑6 as the standard
• Shielding: Dual or quad‑shield (quad for noisy environments or long runs)
• Center conductor: Copper-clad steel is standard for CATV/satellite
• Jacket:
  • Indoor: standard PVC
  • Outdoor/direct sunlight: UV-resistant and outdoor-rated
  • Underground: direct-burial or use in conduit

Use high-quality compression connectors rated for RG‑6 and matched to 75 Ω systems.

Coax for Broadband Internet (Cable Modems)

Cable internet uses similar frequencies to digital cable TV, but is more sensitive to noise and reflections.

Recommended specs:

• Impedance: 75 Ω
• Type: High-quality RG‑6
• Shielding: Prefer quad-shield RG‑6 from the service entry to the modem
• Low-loss: Check attenuation ratings; avoid cheap, thin, or “mystery” coax
• Connectors: Compression F‑connectors; avoid push-on or twist-on types

Minimize:

• Unnecessary splitters between the demarcation point and the modem
• Sharp bends or kinks that can change the characteristic impedance
• Mixing old RG‑59 segments with new RG‑6 on the same line

Coax for CCTV (Analog, HD-CVI, TVI, AHD)

For CCTV, the big concerns are:

• Maintaining image clarity over distance
• Avoiding interference from power, lighting, and other cables
• Supporting HD video formats where required

Recommended specs (modern CCTV):

• Impedance: 75 Ω
• Type:
  • Short indoor analog SD runs: RG‑59 can be acceptable
  • HD‑CVI, TVI, AHD, and longer runs: RG‑6 or high-quality RG‑59 with solid copper
• Shielding:
  • Minimum: foil + braid
  • Prefer high-coverage braid and robust shielding in noisy environments
    
• Center conductor: For CCTV, solid bare copper is preferred over copper-clad for better performance, especially over long runs and when the cable also carries power (in Siamese designs).

If power and video are combined in one cable (Siamese coax):

• Use CCTV-rated Siamese coax with solid copper conductor for the video and sufficient gauge conductors for power (commonly 18 AWG).

Coaxial Cable Comparison Table: RG‑6 vs RG‑59

Below is a practical comparison to help you choose quickly.

Spec / Feature	RG‑6	RG‑59
Impedance	75 Ω	75 Ω
Typical Applications	TV, satellite, cable internet, HD CCTV	Legacy CCTV, short-run baseband/analog video
Signal Loss (attenuation)	Lower: better for high frequencies & long runs	Higher: more loss at CATV/satellite frequencies
Center Conductor	Copper-clad steel (TV/broadband), sometimes solid copper	Often solid copper for CCTV, but varies
Diameter	Larger	Smaller, more flexible
Shielding Options	Often solid copper for CCTV, but it varies	Commonly single or dual-shield; premium variants available
Best Use Cases	New TV/satellite installs, broadband modem feeds, modern HD CCTV	Short analog CCTV runs, legacy or specialty uses
Typical Residential Choice	Yes – standard choice	Only when specifically required or replacing like-for-like

How to Read a Coaxial Cable Specification Sheet

When you look at a coax product page or datasheet, focus on:

1. Impedance: Must match your system (almost always 75 Ω for TV/internet/CCTV).
2. Type: Clearly labeled as RG‑6 or RG‑59, not just “coax.”
3. Center conductor material:
   • TV/broadband: copper-clad steel is fine.
   • CCTV/power: prefer solid bare copper.
4. Shielding: Look for foil + high-coverage braid; consider quad-shield for noisy environments.
5. Attenuation: Lower dB/100 ft at your operating frequency is better—especially for long runs.
6. Jacket rating:
   • CM/CL2/CL3 for general indoor low-voltage
   • Plenum (CMP) for air-handling spaces where code requires it
   • Outdoor/UV-rated for exterior use
   • Direct-burial for underground runs without conduit

If you prefer a single, consolidated overview of these terms across all cable types (Ethernet, speaker, coax, and more), check the main guide: The Only Cable Specification Guide You’ll Ever Need.

Why Choose Zable Cable for Coax?

You can buy coax anywhere, but the difference shows up once the system is turned on. Cheap, off-brand coax often hides:

• Poor shielding coverage
• Inconsistent impedance
• Mixed or mislabeled materials
• Higher real-world signal loss than advertised

Zable Cable focuses on spec-backed, installer-grade coax:

• Clearly labeled RG‑6 / RG‑59 with 75 Ω impedance
• High-quality shielding (dual or quad-shield options for high-noise environments)
• Solid copper center conductors available for CCTV and long-run applications
• Code-compliant jackets (indoor, outdoor, plenum, or direct-burial where needed)
• Performance specs (attenuation, shielding) that match what’s printed on the box

If you want to stop guessing at coaxial cable specifications and just get wiring that works, specify Zable Cable for your next TV, broadband, or CCTV project.

FAQs About Coaxial Cable Specifications

References

1: Science Direct, “Coaxial Cable, ” https://www.sciencedirect.com/topics/engineering/coaxial-cable

2: Research Gate, “Coaxial Cables, ” https://www.researchgate.net/publication/351268180_Coaxial_Cables

3: Scribd, “Coaxial Cables and Applications, ” https://www.scribd.com/document/905753471/Coaxial-Cables-and-Applications