TECHOMAN GUIDE: RF Coaxial Cable Outdoors: What You Need to Know
What is Coaxial Cable?
- Purpose: Carrier radio frequency (RF) signals from a radio receiver or transmitter to the antenna.
- Structure: Inner conductor ➝ insulation ➝ shielding ➝ outer jacket (weather protection).
How Long Does Outdoor Coax Cable Last?
- General Range: 3 to 15 years
- Average for Quality Installations: 5–10 years
- For Critical Systems: Replace every 3–5 years proactively.
What Causes Coax to Deteriorate Outside?
- UV exposure & weather: Sun, rain, snow, temperature swings break down the jacket and internal insulation.
- Moisture: Causes corrosion in copper conductors and connectors.
- Poor materials: Cheap or indoor-rated coax breaks down much faster.
- Improper installation: Tight bends, poor sealing, or loose hanging accelerates failure.
- Physical wear: Movement, wind, or pests can damage cable and jacket.
Signs Your Coax Is Failing
- Cracked or brittle outer jacket
- Corrosion or greenish discoloration at connectors
- Stiff or hardened cable
- Reduced signal strength or reception
- SWR (Standing Wave Ratio) rises
- Water ingress (you may even see it!)
Best Practices to Maximize Lifespan
- Use outdoor-rated coax (e.g., with PE jacket, UV & water resistance)
- Protect connectors: Use coax sealant, shrink tubing, or weather boots
- Secure cable: Use UV-resistant clips; avoid sharp bends
- Bury in conduit for extra protection
- Inspect annually: Check for damage, test signal and SWR regularly
When to Replace Coax
- Visible damage or cracking
- Signal loss increases (often the result of increasing SWR readings)
- Cable is over 5–8 years old (and exposed)
- You notice unusual performance drops in radio reception
Conclusion
Outdoor coax won’t last forever - especially in harsh weather. But with smart cable choices, protective installation, and periodic inspections, you can stretch that life closer to 10-15 years. Still, expect to replace outdoor coax every 5-10 years to maintain peak performance.
Pro tip: Spend a little more on high-quality, weather-rated coax now — it’ll save you signal problems (and headaches) down the line.