What is VHF?
VHF (Very High Frequency) is the name of the radio waves between 30 and 300MHz. Some radio, television broadcasts or radio broadcasts are performed using this frequency band. Apart from these, there are many technical uses such as radio modems, amateur stations, air traffic control
and so on. How much
coverage? In radio systems, coverage can vary depending on the fully used hardware, the antenna's altitude and weather conditions. But in ideal conditions, a sea radio with 25 Watt output power can be effective at approx. 50-60NM (nautical mile-90-110km). However, it can provide effective calls at 9-10NM (15-18km) with an antenna mounted on a small boat (not mounted too high from the sea).
What is a VHF marine radio?
Sea Radio (Marin Radio-VHF Marine Radio), radio telephone system with different names such as the VHF frequency band, the sea vehicles are used to negotiate with each other or land is the radio system. This system uses frequencies between 156-174MHz in the VHF frequency band.
Used for what purpose?
The main purpose of the VHF Marine Radio is to provide the communication of marine vessels within the coverage area. However, all kinds of search and rescue works are also used for the purposes of hazardous conditions in the sea, emergencies, information and weather conditions. Be
low you can find a list of VHF Marine Radio band frequencies set by international authorities for these purposes.
How much coverage?
Speaking of coverage, it is necessary to add a description of the output power of marine radio devices. VHF Marine Radio devices can be 1W or 25W output remote. The reason for this is that there is no need to send a strong signal and overlap with other radio devices in the vicinity (interference) and no unnecessary speech pollution. Like in-port negotiations and negotiations on the ship. 15 and 17 for this purpose. Channels are allocated for use in the ship and can be used for up to 1W power. Except for the 16th. High/Low (high-low) output can be adjusted via the radio device when requested for all channels except emergency-call channel. If you are using an older generation device, you need to change the device's output power from the setting on it, and the new devices are 15 and 17. Automatically select low output power in the channels. 1W power can be interviewed within approx. 2NM (3.5-4km) distance.
What channels are used? VH
F is a total of 55 international channels between 156-174MHz in the VHF band for Marine Radio calls. (between 1-28 and 60-88), 75 and 76 from these channels. Channels 16 for the call and Emergency channel 16. Interaction with the channel (interference) is prohibited. (Update: 75 and 76 according to new regulations. Channels are only opened for use in the power of
1W.) 35 of these channels, the remaining 20 of the DUBLEX works in the same. Duplex channels can be spoken and listening at the same time, Simplex channels can be one-way conversation. You can see a list of them in the table. Sixt
een, basically. Channel (156.800 MHz) is an international emergency, informational and call channel. All hazard, emergency, urgency and safety requests and all calls are made on this channel. When the first contact is c
ontacted against the opposing party in the Normal calls, another appropriate channel number is given and the conversation is resumed from that channel. Except for emergencies, 16. The channel is strictly not used to make calls, it is not occupied. 16. The channel can be occupied for regular calls up to 1min, 10sec for testi
ng and trials. Wireless devices called Dualwatch are also 16. The other channel is listened to while the channel is resting. This is the most practical way to use it.
What is safety communication (Security)?
It is the transfer of important information that affects maritime traffic, can create any negative situation or that sailors in the region must know. This important information can be from the simplest to the weather report in the region or the notification of a non-working lantern, the location of a new float, a newly spotted shlock-rocky, military exercise or underwater work. Safety messag
es are addressed to all stations that can be reached in the region and the 16th of the first call. The entire message and details are published from another channel. (Example: Weather forecast and Storm reports 67. Channel.) The safety
call begins with the repeated 3 times of the word "SECURıTE
". What is Urgency communication?
Urgent messages about the safety of my ship. Issues such as a revolt on the ship, the need for help for a disease condition, a drop in the sea, a rudder or a machine malfunction are covered by urgency. The difference from emergency-emergency is that they are not yet asked for help. Firstly, it is a message published with the aim of informing. Emergency call (Mayday) can be made if the ship's captain is unable to get a result from this briefing. The call for
urgency begins with the repeated three occurrences of the word "PAN PAN". The call call with a medical (medical) situation is done as "PAN PAN MEDıCAL". W
hat is danger-emergency communication? If a shi
p encounters a problem that it cannot solve with its own facilities and requires urgent assistance, it calls for danger. It is the most important call in the radio world. Anyone who hears this call is RESPONSIBLE FOR answering and helping to not compromise their safety! Where the
distress call (MAYDAY) is heard, if there is a place near the shore where the authorities in the land are able to communicate (coastal safety or Coast Guard), all stations that hear the call should be prioritized to ensure the necessary coordination of the coastal Safety or coastal safety. But in case any assistance is needed, the threat is 16. Should follow the status of the chann
el. If the MAYDAY call is an offshore or a distant Kyi outside the area of the black stations, then the responsibility of organizing and helping to organise and assist this emergency communication traffic is on the ships that have heard the call. When an emergency distress c
all is received, the situation is forwarded to the opposite side with the message "RECEıVED MAYDAY". You're not rece
iving an emergency call in the vicinity and you're on 16. If there are stations that use the channel for normal calls, the message "The SYSTEM of Silence" makes a request for the immediate termination of the other conversations in the channel and to
ensure quiet. This request is made by the "SıLENCE MAYDAY" message, which makes the ship or hazard traffic in jeopardy from the d
irection of the land station. At this point, all vessels receiving these calls in the region ARE required to listen to the instructions given by the Black station in the direction of the message traffic and go to help to not compromise their safety when nee
ded/requested. Emergencies-emergency call starts with repeating the word "MAYDAY" 3 times.
The ship's name is given the coordinates of the ship and the time the event/win/situation occurred. Then, respectively, the type of danger, the type of aid needed, details of the hazard, the status of the crew and the weather information is transmitted. Finally, the caller's information is given. If a
boat that is not in danger believes that the help sent is not enough or if the call is not answered, the corresponding hazard message may be repeated 3 times by repeating the message "MAYDAY RELAY". The authorized "
MAYDAY PRUDONCE" call that manages the traffic when the threat is finished or when adequate assistance is provided. When the danger is completely finished, the message "SıLENCE FENNE" is now 16. The channel can be made of normal calls, silence is finished. All these an
nouncements and operations in the old-type radio devices are delivered by speaking sound, while the new type Marine VHF Marine radios, DSC (Digital Selective Calling) with a single button to automatically send hazard signal, ship information and coordinates sent Has a DRESS ke
y. Priority ranking is always as follows;-Ha
zard calls, hazard messages and traffic,-urgency
What is NAVTEX (Navigational Telex)?
Navtex MF (Medium Frequency) is a system that enables the transfer of urgency, safety, meteorology and various warnings from land to ships. The system operates on the MF band with a narrow band direct-write Telegraph (NBDP-Narrow Band Direct Printing) at a frequency of 518KHz and can be taken at a distance of approx. 400NM (740km). The broadcasting stations of each country will broadcast this information in the English language, with an intermediate time of 4 hours. This information is published for all ships for free. The Navtex receiver on the ship automatically receives and prints messages of interest. It is a useful system in remote and international waters where VHF system is not working for all vessels.
What is EPIRB and SART? How does it work? What works?
EPIRB Emergency Location Radio transmitter (Emercency Position, Radio Beacon) as the name suggests, the device will require the ship to be abandoned (sinking, fire, etc.) when an emergency is made by hand-activated according to the situation ( or automatic thinking in water), floating in the sea, giving the illuminated visual warning (Flash) and broadcasting emergency signals from the frequencies of 406MHz/121.5 MHz is a device that allows to be detected by satellite and black stations. The EPIRB emergency signals al
l over the world are monitored by SARSAT (France-Canada) and COSPAT (Russia) satellite systems and when a signal is received, it detects the location with a sensitivity of 2-5km and forwards it to the relevant (nearest) emergency call recovery units. The EPIRB devices contain all the information (name, call code, flag, etc.) of the boat on which they are assembled, so that the fastest and proper search recovery work can be initiated
without delay. The device has a battery system that can operate at le
ast 48 hours. The SART Search and Rescue transceiver (Search and Rescue Transponder) is an active radar reflector (reflector) that broadcasts a trace signal to the radar of the vessels surrounding the emergency ship. Thus, the aid ships arriving at the emergency ship can easily identify the location. When leaving the ship in an emergency, the device is taken to the rescue raft (or next to the people) and operated manually. The device stops at the standby position when it runs, but soon the radar signals have a ship reaching the point where the problem is, it produces special markings that will appear on the radar screen. If there is no ship nearby, the device will no
t work. If there are more than one SART device on a ship, they are not all operated at the same time, they are switched on. The SART devices include battery capacity as long as the 96 clock standby (Standby) + 1 hour broadcast. The waiting time decreases as the broadcast time increases.
The EPIRB and SART are the emergency devices that complement each other, working together in combination with each other. At first, the EPIRB leads the emergency signal through the satellites to the search and rescue teams, and SART helps the search rescue teams from the region easily find the scene.
MARıNE BAND PLAN-FREQUENCY LIST
Channel send frequency receiving frequency Simplex Channel usag
im 1156.050 160.650
D 2156.100 160.700
D 3156.150 160.750 D
4156.200 160.800 D
5156.250 160.850 D
6156.300 156.300 S SEARCH KURTARM
A7 156.350 160.950 D
8156.400 156.400 S COAST GUARD 9
156.4 50156.450 s Fishing channe
l 10156.500 156.500 S fishing chan
nel 11156.550 156.55
0 S 12156.600 156.600
S 13156.650 156.650
S 14156.700 156.700
S 15156.750 156.750 S vessel Internal Use-Max 1W
16 156.800 156.800 s EMERGENCY-CALL/FIRST TEMAS
17 156.850 156.850 S Vessel internal Use-Max 1
W18 156.900 161.500 D
19156.950 161.550 D
20157.000 161.600 d
21157.050 161.550 D 2
2157.100 161.700 D 2
3157.150 161.750 D 24
157.200 161.800 D 25
157.250 161.850 D 261
57.300 161.900 D 2715
7.350 161.950 D 2815
7.400 162.000 D 60 1
56.025 160.625 d 611
56.075 160.675 D 6215
6.125 160.725 D 6315
6.175 160.775 D 64156
.225 160.825 D 65156.
275 160.875 D 66156.
325 160.925 D 67156.3
75 156.375 S METEOROLOGY CHANNEL68 15
6.425 156.425 S 69156.
475 156.475 S Shipyard, shipbuilding and repair. Max. 1 Wat
t70 156.525 156.525 S DSC-EMERGENCY CALL CHANNE
L71 156.575 156.575 S
72156.625 156.625 S YACHT cha
nnel 73156.675 156.675 S YACHT
channel 74156.725 15
6.725 S 76156.825 156.825 S EMERGENCY TELEX CALL C
HANNEL77 156.875 156.875 S fishing
channel 78156.925 1
61.525 D 7 9156.975 1
61.575 D 80157.025 16
1.625 d 81157.075 161
.675 D 82157.125 161.
725 D 83157.175 161.
775 D 84157.225 161.8
25 D 85157.275 161.87
5 D 86157.325 161.925
D 87157.375 161.975 D AıS Systems 1. Chann
el 88157.425 162.025 D AıS Systems 2. Channel