|
|
Resources Below are Evaluated sites that have important information on all aspects of communications . USCG Navigation Center Radio Rules & regulations
International Maritime Organization 
Global Maritime Distress Safety System. GMDSS
|
Marine VHF radio Do not leave the dock without one Every boat should be equipped with a marine VHF radio, this is not a requirement but it is smart. Some would say in this day and age you could use a phone. But do you know the Coast Guards number if you need help. Do you know the phone number of the boat half a mile away? VHF radios are invaluable and with Digital Selective Calling (DSC) we have even more benefits. A DSC equipped VHF radio can send your exact position to rescue services or indeed anyone within VHF range. Rescue can be minutes away if you press that little red button.
Every recreational boat should be equipped with a marine VHF radio, as we
stated before this is not mandated but it is wise. VHFs are the prime means
of communications in local waters i.e. up to 20 miles offshore
see range.
With a VHF you can talk to someone on your own boat, you can talk to another boat, you can call for help, you can listen for maydays, listen to weather alerts, and you can call a ship to help maneuvering in a channel. With an AIS signal you can find the radio call sign of a ship and call them by name.
VHFs are for use in and around the water not for use on land. Want to use the VHF like a walkie-talkie? Then choose one with family radio service (FRS). Standard Horizon HX-471S has FRS channels and can be used on land and water.
How far can you expect your radio to reach? The International Maritime
Organization stipulates VHF range as; Area A1 ; Within Whether you can receive 30 miles offshore is another question and depend on your equipment and weather conditions. VHF stands for very high frequency between 156 and 174MHz. VHF signals travel in straight lines (line of sight) and so range is relatively small.
You can see antennas on both sides influences the quality of reception/broadcast Power; Under average conditions, a 25 watt radio with an 8-foot antenna, range should be within a 12 to 15 mile radius. Weather is the limiting factor. Fixed location radios have a selector switch which alternates between 1- to 25-watts of power, which is an obvious advantage over the lower power of handheld units. Batteries and range; Unless you need the range, set your VHF to minimum power, this will save your battery. "typical operation" of a VHF is normally defined as 5% transmit, 5% receive, and 90% standby. VHF Antenna; It does not matter how much power you have in the radio, if your antenna is too close to the deck. Mount the antenna as high as possible and make it vertical. Antenna Gain; Gain in a VHF Marine antenna is expressed in decibels (dB). Typically marine antennas are 3, 6 or 9DB. The 3 l ie low gain antenna means equal energy distribution in all directions. A 9db antenna has most energy focused 90 degrees to the antenna. Assuming a vertical antenna which is best the 3DB is best for a sailboat, due to heeling and the 9DB is best for powerboats. Here is one resource on Antenna from Boat Project
Choosing a marine VHF radio either a handheld or fixed radio depends on your intended use and the features of the boat. If you are looking for the longest range a fixed mount radio is best. If portability is an issue a handheld is best.
Handhelds are limited to a transmit power of 1-6 watts. For normal handheld use from a small boat due to the low antenna range maybe 3-5 miles. Both the power and antenna height of a fixed mount radio extends this range dramatically
Some modern VHF radios include an onscreen reminder of channel use. Marine VHF channels are County specific and the US is different to some other parts of the world. There are a U.S. group, a Canadian group, and an international group.
Hence if you buy a US radio and use it in Europe you will find some variances. In European inland waterways you will need ATIS, if you buy a radio there it will be included, but not if you buy the radio in the UK for example.
USCG Navigation Center; has full list of vhf radio frequencies showing International, Canadian and US channels. Remember some marine vhf frequencies are not used internationally but only in the US and Canada.
Using a VHF radio is simple, but can be intimidating the fist time. A few basic rules will get you on your way.
Squelch Control; Adjust the squelch till the static goes and then turn up slighly.
Basic call etiquette; Simplex calls go like this. Calling Vessel "Capella" this is vessel "Argo" OVER, and you wait for a response. Each time a party finishes their communication they say OVER which indicates the other party can now respond. Pressing the key allows your conversation to be sent and none comes in.
If you are not making a call you should stay on standby on Channel 16 at all times
series on operating and benefits of VHF
Called "Can your hear me?" this series covers VHF and emergency procedures. If nothing else this primer will let you know all the basics.
You can read and listen to each topic and use the pause/play & fwd and back
buttons. DSC simulation
Simplex and Duplex channels; Duplex refers to a two way conversation like a phone, while simplex means only one side can communicate at a time. Simplex calls go like this. Calling Vessel "Capella" this is vessel "Argo" OVER, and you wait for a response. Each time a party finishes their communication they say OVER which indicates the other party can now respond. Pressing the key allows your conversation to be sent and none comes in.
In the US no formal instruction/training is required, but we give you some resources that will help you learn how to use your VHF. In the UK you need a Short Range Certificate (SRC) to operate a VHF with DSC. A one day course gives you the certificate. Once you have this SRC you will get an MMSI number. In the UK you can take the course at the RYA. This course even covers EPIRBs and SARTs. To learn more about VHF here are some VHF books and online resources;  YachtCom offers an online resource for VHFs. They include a table for range v antennas height. They have lots of other communication material. Their courses are UK based but much of the information is international.
USCG and BoatUS Foundation,
seen above VHF Books; If you want to learn more about using your VHF here are two books. The first is a guide that anyone can read. The second is a more advanced look and includes tutorials and interactive DVD.
Nearly six million U.S. and Canadian recreational sail- and powerboats carry VHF radios. Endorsed by the U.S. Coast Guard and written by a navigation VHF-DSC radio trainer, this user friendly guide gets boaters quickly up to speed on both analog and digital VHF radiotelephone usage. Its straightforward, non technical coverage, "Geek-speak" boxed definitions, quick reference chart, and more make it easy for readers to quickly master and get the most out of their radios. $16.95 and can be got at
MH
Professional  VHF DSC Tutor is for professionals looking to get their radio license. Endorsed by the RYA The SRC course is intensive, seeking to teach or revise
all the basics of Marine VHF then cover all the new equipment and
procedures, usually taking just one day. This new Tutorial has been specially produced to make it much easier
to get the best from the SRC course by covering the basics of VHF and
VHF procedures, then introducing DSC and how it integrates with
established methods. Typical DSC equipment is then examined and all the
button-pushing procedures are animated.
$34 for the tutorial to $168 which includes the tutorial and the simulator
with shared use on PC.
DSC is digital signal which is automatically sent (channel 70) when you press that RED
button. Included in the signal is your position, Not all radios are DSC enabled, some handhelds do have the capacity. There are two types of DSC/VHF radios; Class A and Class D. Class A is for professional mariners, Class D is recreational and the most obvious differentiating feature is that Class A receives DSC signals while transmitting. With Class D if you are transmitting you will not receive a DSC call. You will receive a DSC call if you are receiving however. Who Monitors DSC calls; The US Coast Guard monitors channel 70 DSC. USCG's navcen site explains. Commercial ships over 300 tons are now required to monitor the DSC radio reserved channel 70, for distress calls. You need an MMSI number and a GPS connection to your VHF To enable all the features of DSC .
Test your DSC; To test your DSC capability send a "test" transmission to a Coast Guard stations MMSI number. Cancelling a false alarm a problem with DSC is false alarms, accidentally sending a distress signal. If this happens is no good just turning off the alarm, since the Coast Guard and other vessels have received your distress call. You must broadcast on CH 16 the false alarm. That way USCG and other boats equipped with DSC will know not to respond and send out SAR teams.
Your MMSI number is your unique identity (no one else has this number) and contains important information about you. Obtain your MMSI and program it into your radio. Be careful as you only get one shot at entering.
It is very important to get an MMSI number and to connect a GPS to your VHF. The USCG stats see link reports that 90% of calls received had no position with the signal. Also 60% of calls did not have an MMSI identity number. This means the Coast guard received your emergency call but did not know who you were or where you were. In the UK you will need to take a 1 day course and achieve a short range certificate (SRC). Once you achieve your SRC you will be given a MMSI number.
You can Connect your VHF fixed radio to GPS with 2 wire NMEA cables. Check your radios manual for instructions. This diagram of the Standard Horizon GX1600.
USCG Rescue 21; Rescue 21 revolutionizes how the Coast Guard uses command, control, and communications for all missions within the coastal zone. The system:
Remember connect your VHF to a GPS have both turned on and register for your MMSI number and have it programmed into the VHF. The Rescue 21 VHF/DSC communication system is designed to provide reliable communication with a 1 watt radio, 1 meter above the water, at a distance of up to 20 nautical miles from shore.
If you have all the right gear, VHF, Chartplotter and MMSI number, you can use Position polling.
Position Polling lets you see another boat on your screen. Lets say you are fishing and a friend is also fishing. Imagine cruising with friends and you can have their position right on your chartplotter.
Call them via DSC using their MMSI# and if they respond you will see their position on your chart.
To find out how to use and features of Position Polling click here
Our U.S. Coast Guard-licensed captains are highly skilled professionals with expert knowledge of the waters they patrol. They routinely provide navigational guidance through tricky waterways, share local tide and weather info, and so much more. With Sea Tow's 24/7 availability, members have Peace of Mind on the Water™ knowing that help is the just click of a VHF radio mic or phone call away. In addition to helping you on the water – when you need us most – Sea Tow maintains a network of maritime professionals who help members get more out of boating. Contact Sea Tow for direct access to these exclusive SERVICES, at no additional cost.
The National Boat Owners Association; Hundreds of commercial tow boats committed to assisting NBOA members. NBOA is committed to dispatching the 1st
available boat to assist you in an emergency.
NBOA Dispatch is on duty 24/7/365 answering your calls for assistance. Call 1-800-234-2869 via your cell phone or the marine operator vhf radio and NBOA's dispatcher will do the rest.
NBOA towing service is available anywhere in the continental USA. NBOA will dispatch a tower to assist you where ever you are.
Used
Boat Parts
|
|
|
|
Home | Newsletters | About | FAQ | Contact Us | Site Map
range of VHF coast stations with continuous DSC alerting available (about 20-30 miles) 
and
boat name.
