A VHF radio is one of the most cost-effective safety items you can have on your boat. They allow you to easily communicate with the U.S. Coast Guard, commercial ships, and the Rescue 21 network.
VHF radios also offer DSC, which allows you to broadcast a distress signal automatically at the push of a button. Unlike UHF, VHF waves can penetrate through trees and rugged terrain.
VHF Radio Antennas
VHF radio equipment is a valuable tool for boaters in many ways. Handheld VHF radio can help you make telephone calls to shore, summon rescue services, or contact harbors, locks, and bridges for operating information. VHF radios also broadcast maritime safety warnings.
Unlike cellular phones, most handheld VHFs can communicate with multiple people simultaneously or call for emergency assistance on dedicated channels like channel 70. They can also transmit your Maritime Mobile Service Identity (MMSI),, letting other mariners find and identify your vessel when you call.
The type of antenna you need depends on the environment in which you’ll be using it. Antenna height directly affects range because VHF waves travel in what’s known as line-of-sight. A taller antenna will have an excellent range because it can see farther over the horizon. Gain is another crucial factor that measures how well an antenna concentrates a signal. A higher gain antenna will increase signal strength by doubling it or more.
VHF Radios
VHF radios operate on the frequency spectrum of 30 to 300 megahertz and are ideally suited for scenarios where transmitted radio waves don’t travel more than 160 kilometers (100 miles). They transmit weather alerts and hazards to navigation through Channel 16 and summon marine rescue services via Mayday calls.
When using a marine VHF radio, it is important to remember proper communication etiquette. For example, if you are a pleasure boater communicating with other recreational boaters, limiting non-emergency conversation to Channel 9 is best. Additionally, it is unacceptable to broadcast your personal information, such as your name or address, over the radio. Instead, it would help if you used cryptic call signs.
Marine VHF radios often have specialized marine features such as built-in GPS and Digital Selective Calling. They also offer AIS (Automatic Identification System) functionality that automatically sends your vessel’s location to the Coast Guard at the push of a button.
VHF Cell Phones
Cell phones are great to have on hand, but they should not be your primary method of communication at sea. A VHF radio is much better when you need to report an emergency or call for help.
A VHF marine radio will reach the Coast Guard or an on-water towing company — even if your cell phone is out of service. Plus, VHF marine radios have built-in Digital Selective Calling (DSC) technology that will alert nearby boats to your distress signal and their unique Maritime Mobile Service Identity number at the push of a button.
Tune your VHF radio to Channel 16, the international distress and safety frequency. Then repeat your mayday signal or activate your EPIRB. A Coast Guard watchstander will receive your call and dispatch a search and rescue team immediately. That’s how a VHF radio can save your life, while a cell phone can waste precious time in an emergency.
VHF Accessories
A VHF is your lifeline to shore, whether on a sailboat or a tug boat. It facilitates communication between boats, marinas, bridges, and Coast Guard stations. It is also vital for emergency and hailing calls.
A marine VHF radio is a combined transmitter and receiver that operates on international, standard frequencies known as channels. A radio can operate as a full duplex, transmitting in one direction and receiving in the other, or it may be set as a semi-duplex so that it only transmits when you press the transmit button.
Some radios are equipped with Digital Selective Calling (DSC), the modern equivalent of a mayday button. When activated, a radio with DSC broadcasts an encoded distress signal that is automatically picked up by all DSC-equipped vessels. This can speed up rescue response time.
