Coax Cable & Extensions
Seachoice 19781 5' RG58U White Coaxial Antenna Cable Assembly with PL259 Fittings
Seachoice 19761 10' RG58U White Coaxial Antenna Cable Assembly with PL259 Fittings
Why Coax Cable Matters for Marine & RV Electronics
When you're out on the water or the open road, the strength and clarity of your radio communications can be a matter of safety. Coaxial cable and extensions are the critical link between your VHF radio, GPS, AIS receiver, or AM/FM antenna and the electronics that process those signals. A degraded or improperly rated cable can rob your antenna system of performance before the signal ever reaches your receiver — making the right cable choice every bit as important as the antenna itself.
Marine and RV environments are among the harshest conditions coax cable can face. Salt air, UV radiation, constant vibration, and moisture all conspire to degrade signal quality and corrode connections over time. This is why marine-grade coaxial cable is purpose-built to handle these stresses, with robust outer jackets, corrosion-resistant connectors, and low-loss construction optimized for the frequencies your onboard electronics depend on.
What to Look for in Marine Coax Cable
Not all coax cable is created equal. Here are the key considerations when shopping this category:
- Impedance: The standard for marine VHF installations is 50-ohm coaxial cable — the entire marine antenna and radio ecosystem is built around this specification.
- Cable Type: RG-58U is widely used for shorter runs and standard VHF applications, while RG-8X offers improved flexibility and lower loss for longer cable runs inside masts or bulkheads.
- Connectors: The PL-259 (SO-239) connector is the overwhelming standard for marine VHF radios. Look for assemblies with pre-installed, corrosion-resistant connectors to simplify installation.
- Length: Signal loss increases with cable length, so choose the shortest run that reaches from your radio to your antenna. Pre-assembled cables come in common lengths — typically 5, 10, and 20 feet — to suit most installations.
- Marine Rating: Always choose cable specifically rated for marine or RV use, with UV-resistant jacketing and corrosion-proof hardware at connection points.
Top Brands in Marine Coax Cable & Extensions
Seachoice is a trusted name in marine accessories offering a comprehensive range of coaxial cable solutions. Their lineup includes RG58U white coaxial cable assemblies with PL-259 fittings on both ends, as well as marine-grade L-195 cable extensions designed for VHF antennas fitted with ProConnect FME connectors. Seachoice's coax products are built to deliver reliable signal transmission in demanding marine and mobile environments.
Sea-Dog Line brings decades of marine hardware expertise to the coax cable segment. Their coaxial cable assemblies feature RG-58U cable pre-assembled with nickel-plated brass PL-259 fittings on both ends, allowing for quick, tool-free installation on VHF antenna systems — a practical choice for boaters who want a clean, dependable connection without custom fabrication.
Shakespeare Antennas is one of the marine industry's most recognized antenna brands, and their coax cable lineup is a natural complement to their antenna systems. Shakespeare offers low-loss cable options spanning VHF, AM/FM, and SiriusXM antenna needs, as well as their innovative Centerpin® solderless connectors that simplify installation without soldering — an ideal solution for boaters and RV owners setting up or extending their antenna systems.