Communications

Reliable marine communications equipment is vital to the success and safety of offshore boaters around the globe. The United States Coast Guard believes that a VHF radio is the single most important radio system you can buy for your boat. VHF radio channel 16 (for voice) and channel 70 (for DSC) are monitored 24 hours a day by the U.S.C.G. So from chatting with fellow boaters to making a serious distress call, a quality VHF radio is essential to your safety onboard. However, if you plan to travel more than a few miles offshore, it's also recommended that you purchase a mobile satellite telephone system or an MF/HF radio telephone. Unlike traditional VHF radios, satellite equipment will provide a reliable connection in even the most remote offshore areas. Plan on purchasing this type of equipment if you venture more than 20 miles offshore to ensure proper coverage. Not sure which communications equipment is right for you? Give us a call, and our experts will help you determine which product best fits your needs.

Fixed Mount VHF Radios

Fixed Mount VHF radios are an essential electronic to vessels of every size. By requirement, all VHF radios offer a 1-watt output capability in addition to the noted maximum output (typically 25 Watt) with each unit. All also have reduced out put on channels 13 and 67 by requirement, and all include US, International, and weather channels. We recommend that all VHF radios, other than those specifically noted as “waterproof” or “submersible”, be mounted in a protected place. Many Fixed Mount VHF radios feature remote microphones that duplicate the function of the base VHF radios, creating true second and, in some cases, third stations. These remote microphone options are the perfect answer to expanding the communication capability on your boat at a reasonable expense. The main radio console can be installed in an electronics box protected from the elements and a remote, full-function, second station can be installed to optimize limited space on your dash. Fixed-mount VHF communication technology has also advanced with the integration of DSC (Digital Selective Calling). When you activated, your MMSI number is embedded in the distress broadcast and the SAR team will know who is sending the distress call. And when connected to your GPS via a NMEA interface, the DSC distress signal will also automatically broadcast your Lat/Lon position. To enable this system you must first apply for a MMSI (Maritime Mobile Safety Identity Number) identification number. This number is embedded in your radio and is your unique number. Boaters can apply for their free MMSI number by visiting seatow.com and following the MMSI links. This provides for a dedicated second receiver that continuously monitors channel 70 for distress calls.

Hailers

With one of our loud hailers you will be able to have access to ship-to-ship communications. You can also hook these up to intercom speakers and use this as your own personal intercom system. These are required for a lot of commercial vessels but it is not uncommon for the recreational boater to have one as well. Also, don’t forget to add at least one hailer horn with each purchase of a loud hailer.

Antenna Gain

Antennas are easily distinguished from one another by its effective radiating power (ERP). Expressed in decibels (dB), marine antennas most commonly rate as 3, 6, or 9dB, with the general rule being “the higher the gain, the longer the range”. You must consider the length of your boat when choosing which gain you want since the width of the transmission beam narrows as the decibels increase. Typically, smaller fishing boats operate with a 3 or 6dB gain while larger, more stable vessels take advantage of a 9db gain antenna.


Below are simple formulas that will assist you in selecting the best antenna for your needs:

3dB: Antenna height (in feet) about the water line x 1.15 = range in nautical miles

6dB: Antenna height (in feet) above the water line x 1.42 = range in nautical miles

9dB: Antenna height (in feet) above the water line x 1.52 = range in nautical miles



Antenna Mounting and Installation Tips:

• Do not mount your antenna near fluorescent lights
• Antenna cable should be a minimum of 3 feet away from other electronic equipment
such as transducers, engines, plasma TVs, and other radio and navigation antennas
• Prevent interference or magnetic anomalies by cutting excess coaxial cable
• Do not skimp on hardware. Using top quality connectors and cables will optimize your VHF system.