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All afloat vessels rely on the VHF radio as the primary means of communication with the world around them.
VHF radio is the main tool on board that allows boats of all kinds to communicate easily with the unique unplugged world around them. Big container ships, working barges, fishing trawlers, sailboats, motorboats, and the Coast Guard all rely on this single tool as their primary source of communication.

For us pleasure sailors, the VHF radio serves us in many useful ways. We're able to speak with oncoming boat traffic, hail bridge tenders for openings, or make arrangements with marinas along the way. If we're rendezvousing with friends miles away, we can update them on our whereabouts. When it comes to checking on the forecast, the majority of boaters turn to the VHF as their primary resource for getting marine weather information. Most important of all though, the VHF radio is there for us should we ever need to make a distress call.

Cellular phones seem to be on almost every boat on the water these days, but don't be confused into thinking they can be utilized as a replacement for the VHF radio. If there's a boat two miles away and you need help, your cell phone is not going to do you any good. With VHF radio you're able to hail that vessel, or possibly even hundred of others-without knowing a single phone number.

While a handheld VHF radio may be adequate for certain limited distance applications, anyone who wants better range in both transmitting and receiving will definitely want to permanently install a VHF radio. Many cruisers like us have two permanently installed VHF radios plus a handheld.

"The process of installing a VHF radio and antenna is one that most sailors can undertake themselves."
The process of installing a VHF radio and antenna is one that most sailors can undertake themselves. In addition to the radio and antenna element, you'll need coaxial cable, end fittings for the cable called PL-259 connectors, and a thru-deck fitting for the cable if your mast is deck stepped or if you plan to mount the antenna on a stern rail. When shopping for a VHF radio, keep in mind that all radios designed for recreational boating are 25 watts output radios and must by law feature a one watt "low power" setting. The difference in cost of various radios is attributed to the extra features and functions. After reading about the different radios choose a brand and model that offers the right combination of optional features to suite your needs and budget.


Choose a mounting location for your radio that is convenient and that minimizes the lenght of cable from the antenna to the radio and the length of the power wires.
In the initial stages of planning your radio installation you'll want to take into account several factors. For best performance, the cable run from the antenna to the radio should be as direct and as possible, and likewise for the wires providing power to the radio. Try to choose a mounting location for the radio that provides the best combination of convenience to the user while maintaining the shortest possible runs.

On smaller sailboats a mounting spot just inside the companionway allows you to reach the radio whether you are down below or in the cockpit, plus it keeps the transceiver out of the weather. Some VHF radio manufacturers provide a flush mount kit for their radios. This gives you the option of cutting a hole in the cabinetry at some location and mounting the radio so that the face is flush with that surface. The standard bracket supplied with most radios screws easily into any flat surface and allows you to tilt the face up and down for easy use.

Larger sailboats almost always have a VHF mounted at the nav station below, and often you'll see a second one in the cockpit. This second station can be configured in one of several ways. Some of the newer radios offer as an option a full function microphone that can be set up at a remote location. This remote microphone works with your primary radio and lets you control all important functions. Another option is to install a second entire radio. If you mount a second radio, you have the choice of sharing your existing antenna with your primary radio by installing a splitter in the coaxial cable or you can add a second dedicated antenna. Any time you add things like signal splitters or additional connectors to your coaxial cable, you weaken the signal. We think it's best to install a second stand alone radio and independent antenna to provide backup communication should it ever be needed.


The higher the VHF antenna is, the greater will be the range for transmitting and receiving.
When choosing a location to mount your antenna, keep in mind VHF radio signals travel in a straight line. Simply put, the higher you mount your antenna the greater your range for both transmitting and receiving. For us sailors, that means mounting our antenna at the top of our mast for best performance. Antennas designed for mounting at this location are about three feet in length, provide low wind resistance and are lightweight. The masthead antenna on our sailboat, Serengeti, is 60 feet high and provides us an approximate 27 to 29-mile range of communication with other sailboats of similar size, while our deck level antenna limits us to a range of around eight miles.

All antennas are rated in something called dB gain. dB gain refers to an antenna's signal pattern and its ability to focus energy. Always select a three dB gain antenna for sailboat installation because it minimizes signal loss that can result from pitching and rolling.


The most important potential use of the VHF is the ability to make a distress call should the need ever arise.
If you've decided to mast mount your VHF antenna, you can either work from a bosun's chair or un-step the mast and work at ground level. Some mastheads are built or have been fitted with a flat area that provides a mounting surface for accessories like a VHF antenna, wind indicator, etc. If you don't have such an area, you can drill and tap the side of the mast just below the masthead fitting and mount the antenna with the bracket provided by the manufacturer. Always use stainless steel screws and isolate the dissimilar metals like stainless screws in an aluminum mast with a product like Tef-gel.

Coax cable carries the energy created from the radio to the antenna. If you buy cheap cable for your installation, you're eventually going to have a weak signal. Choose a coaxial cable designed for marine use. The conductors are tinned, and will last much longer in the moist and salty environment. Because connections are always the weakest point in any installation, take extra care to maintain their integrity by coating the outside of the finished connection with petroleum jelly and covering with a length of heat shrink tubing. Don't forget to slide the heat shrink tube onto the cable before you make the connection.

"Before running the coax cable, you need to determine whether your mast was built with an internal conduit."
When it comes to running the coax cable you first need to determine whether your mast was built with an internal conduit for the purpose of running wiring. If a conduit is present, you already have a path for the cable that will eliminate it from flopping around inside the mast. You may need to drill a hole in the top or side of your mast to allow entry of the coax cable. Press a rubber grommet into this hole to prevent chafe of the wire. If working from a bosun's chair, drop a small line with a fishing weight or heavy bolt attached to it through the mast or conduit, then tie and tape this line to the cable to pull it along the same route. If your mast is un-stepped push an electrician's fish through the mast, then attach the cable to the fish and pull it back through.

If your mast is deck stepped, you'll need to install a thru-deck fitting adjacent to the mast step. In the length of cable where it exits the mast and enters the deck be sure to leave enough cable to fashion a drip loop. A drip loop is an S-shaped bend in the cable that encourages water to fall off the cable and onto the deck before it reaches the deck fitting.

VHF antennas mounted at deck level are normally positioned back on the stern rail so that they are clear of all the running rigging. Special rail mounts are sold for attaching antennas to 7/8 or one-inch stainless tubing, and a thru-deck fitting is employed to bring the coax cable into the boat. Deck mounting your VHF antenna is a more simple procedure. It's a good option if you don't need long range communication from the radio or if you're looking for system redundancy in an offshore boat.


Once your VHF is installed, take some time to familiarize yourself with the rules and regulations that govern its usage.
With your radio secure below and the antenna and cable installed, it's time to make the power connections. Depending upon your mounting location and the complexity of your electrical system, you'll either be running your wiring straight to the battery or to a breaker/fuse panel. Regardless of the source of power, be certain that the positive power lead is fused according to the manufacturer's recommendations. If you find that the wiring harness provided with the radio is of inadequate length, you can extend it with crimp connections and the appropriate additional amount of wire. As with the coaxial cable, it's best to use wire designed to hold up in the marine environment. Make sure the wire is tinned and the size of 12 ga. should be more than adequate.

Once your new VHF radio installation is complete take the time to make sure you are familiar with the rules and regulations that govern the use of VHF radios. These rules are designed so that all mariners can communicate with each other in an orderly fashion and ensure that safety concerns always have priority. If you're not sure of which channels to use or how to properly hail, check out our previous article here at SailNet entitled "VHF Radio: Usage and Etiquette." Enjoy your new radio and safer boating.
 
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