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Marine VHF Radio. Course to prepare for Restricted Certificate of Competency Supplied courtesy of Ger Keeling. Course Objectives. To give a brief introduction to the basic principles of radio. To relate these to Marine VHF Radio use
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Marine VHF Radio Course to prepare for Restricted Certificate of Competency Supplied courtesy of Ger Keeling
Course Objectives • To give a brief introduction to the basic principles of radio. • To relate these to Marine VHF Radio use • To acquaint participants with procedural and general radio conversation • To give an understanding of the use of radio for safety of life at sea • To prepare participants for the Department of Communications examination for the award of a Restricted Certificate of Competence (VHF only)
Marine Radio • Radio offered the only option for communication with at sea • Ensuring the safety of seafarers was to be the primary concern • Early signal transmissions were by Morse Code and later by modulated voice transmissions • The first known “CDQ” signal was sent by the SS “Titanic” • The CDQ was replaced by the more familiar SOS
Modern Marine Radio • There are a number of radio bands allocated specifically for marine use. The main ones are 415 -- 535 kHz Morse Telegraphy 1606 -- 2850 kHz MF Marine Radio Telephony 4 -- 28 mHz HF Marine Radio Telephony 156 -- 162 mHz VHF Marine Radio Telephony
Easy to use Good clear reception Reasonable range of coverage for small vessels Most vessels over 10 metres are fitted with VHF sets Low power requirements make battery operation possible VHF facilitates reasonable antenna sizes Portable and handheld sets are readily available The Relatively low cost of appliances has lead to their great popularity Marine VHF Radio
Control of Marine VHF Radio • In the Republic of Ireland the use of Marine VHF is controlled by the Minister for Communications • The laws are applicable within the state and on Irish registered vessels • The owner is responsible for ensuring that the set is licensed and that the conditions of license are observed. See Appendix 1 • Condition 7 requires that the radio installation may only be operated by persons holding valid Certificates of Competence
Formality of Procedures • English is the international language of marine communication • Marine VHF radio is used by many people who do not naturally speak English • Radio conversations are not as interactive as normal person to person speech • Conversation must be as short as possible • As many conversations are safety related, there is a need to have un-ambiguous and precise dialogue
Station Identity • It is compulsory to identify yourself on every transmission • When a Radio Installation is licensed, a registered Call Sign is issued • This will be some combination of letters and numbers, which is internationally registered. • Irish Call Signs are generally in the form EI XXXX • It is acceptable to use the vessel’s name or a combination of both the name and call sign.
General format of message Name of station being called and call sign (if applicable) Repeat up to three times This is Name of calling station and call sign (if applicable) Repeat up to three times Message to be sent Over
“Pro” words and other common phrases I copy or Copied Seelonce Prudonce This is Stand By Stand By one Over Mayday Out My position is Pan Pan Station Calling -- ? Traffic Securite Say again Word before -- Word after -- TR Mayday Relay UTC Unreadable Signal Strength All before --- All after -- All Stations ETA I say again -- ETD Received SAR Nothing Heard
The Phonetic Alphabet A Alpha B Bravo C Charlie D Delta E Echo F Foxtrot G Golf H Hotel I India J Juliet K Kilo L Lima M Mike N November O Oscar P Papa Q Quebec R Romeo S Sierra T Tango U Uniform V Victor W Whiskey X X-Ray Y Yankee Z Zulu
Phonetic Numerals 1 Won 2 Too 3 Tree 4 Fow-er 5 Fife 6 Six 7 Sev-en 8 Ate 9 Niner 0 Zero The number 294.8 would be stated as follows TOO NINER FOWER DECIMAL ATE
Stating Time and Position “My Position isFIFE TREE ZERO NINER DECIMAL ATE North ZERO SIX ZERO FIFE DECIMAL TREEWest” or “My Position isTOO miles bearingTOO NINER FIFEfrom Moulditch Buoy” Time “TOO WON ZERO NINERUTC” 21:30 or 09:30 p.m. GMT 22:30 or 10:30 p.m. BST
Precautions before transmitting • Who is the call intended for • Is the selected channel correct for the message to be sent and what working channel is appropriate • Be sure that the channel is not being used and that there is no higher priority incident in progress • Are you authorised to make the call • Have you composed the message in your mind
Channel 16 Emergency Channel Initial Calling Channel Once contact is made stations must switch to a suitable working channel Priority must be given to more important traffic Inter Ship Channels 6 8 10 72 73 Port Operations 12 14 11 09 68 71 Small Boat Safety 67 Coastal Radio Station 83 Dublin 87 Wicklow 23 Rosslare Channel Allocation
Marina / Race Control 80 (37 M M2) Digital Selective Calling 70 Do not use for voice CH 16 Guard band 75 76 May not be used US Channels Used for weather CoastGuard contact etc. 7A 18A 19A 21A 22A These use one half of an international Duplex channel (explained later) Channel Allocation
Good Radio Manners • Always listen before transmitting • Keep conversations short as possible • Make sure that your message is clear • Use “Pro” words and sound professional and competent • Obey instructions from coast stations (or more competent operators) • Speak calmly and clearly • Do not use bad language, CB talk, TV cop habits or people’s personal names
What is Radio • Radio is a type of natural radiated energy, known as Electro-magnetic Radiation (EMR) • Since it’s discovery, we have learned to transmit and receive it and harness it for many uses. Other EMR Radio EMR Radio Broadcasts TV Broadcasts Communications RADAR Microwave Ovens Visibe Light Infra Red Light Ultra Violet Light X-Rays Lasers - are all forms of Electro-Magnetic Radiation
EMR’s Wave-like Behaviour Wave Length The distance between two adjacent peaks [ Metres ] Frequency The number of peaks which pass a point in a second [ Hertz ]
Wavelength • Nowadays we tend to describe radio waves in terms of frequency rather than wavelength • Wavelength is more commonly used to describe the higher frequency waves.. e.g. microwaves or lasers and visible light • The wavelength of radio is however relevant to the size of the antenna or aerial • Longer wave lengths require huge antennae whereas higher frequencies (shorter wave lengths) require more sophisticated electronics
Long Wavelength -- Low frequency 30 KHz -- 10Kilometers Short wavelength -- High Frequency 30GHZ -- 1centimeter Frequency vs. Wavelength
Frequency 1 Hertz Hz 1 Cycle per second 1 Kilo Hertz KHz 1,000 Cycles per second 1 Mega Hertz MHz 1,000,000 Cycles per second 1 Giga Hertz GHz 1,000,000,000 Cycles per second 1 Tera Hertz THz 1,000,000,000,000 Cycles per second
Signal Propagation Frequencies below approx 3Mhz follow along the earth’s curved surface and are therefore described as “Ground Waves” ( e.g. Long and Medium Wave radio broadcasts)
Short Wave Propogation The earth’s atmosphere is surrounded by layers of charged gas particles, referred to as the “Ionosphere” Frequencies between approx 3Mhz and 30Mhz tend to reflect off the Ionosphere. These are described as “Sky Waves” (also Short Wave or HF)
VHF/UHF/SHF Propogation Frequencies above approx 50 MHz are limited to “Line of Sight” and are therefore useful for local, aviation and celestial uses.
Ground Wave Uses Long Range Communications Marine Medium Frequency Marine Morse Telegraphy Medium Wave Radio Long Wave Radio 30 KHz 300 KHz 1 MHz 2 MHz 3 MHz 10 KM 1 KM 100 M
Basic RadioTransmitter Transmitter 157.0 MHz
Basic Radio Receiver Receiver only listens to signals on it’s tuned frequency. Receiver 157.0 MHz
Transmitting a Signal Transmitter Receiver 157.0 MHz 157.0 MHz
Transmitting “Sound” Waves Sound Sound Wave Modulation Transmitted Radio Signal Radio Wave The sound wave is “modulated” on to the “Carrier” frequency Radio Wave Transmitter 157.0 MHz
De-modulation Receiving “Sound” Waves Radio Wave Receiver Receiver only listens to signals on it’s tuned frequency 157.0 MHz Sound Wave Sound
156.0 MHz 156.0 MHz The Radio Tranceiver Common Antenna Receiver Speaker Receiving The “Push to Talk” (PTT) Button Normally On Radio Wave Normally Off Transmitter Microphone
156.0 MHz 156.0 MHz The Radio Tranceiver Common Antenna Receiver Speaker Off when pressed The “Push to Talk” (PTT) Button Radio Wave On when pressed Transmitting Transmitter Microphone
156.0 MHz 156.0 MHz Squelch Control On/Off/ Volume Receiver Normally On Channel Selector Radio Wave Normally Off Transmitter High / Low Power
156.0 MHz 156.0 MHz Squelch On/Off Volume Receiver Noise Message Normally On Silence Radio Wave Normally Off Transmitter Receiving
156.375 MHz 156.0 MHz 157.0 MHz 156.375 MHz 156.0 MHz 157.0 MHz Ch 83 Channel Select Ch 67 Ch 16 Ch 0 161.775 MHz Receiver 156.8 MHz off PTT Button Radio Wave on 157.175 MHz Transmitter 156.8 MHz
Calling another Station Name of station being called and call sign (if applicable) Repeat up to three times Ross Turk, This is Name of calling station and call sign (if applicable) Repeat up to three times Misha, Misha Message to be sent Channel Six Over Typical Example only !! If no response, wait for approx three minutes and try again.
Response to a Call Name of station being respondingto call sign (if applicable) Mise, This is Name of responding station and call sign (if applicable) Ross Turk, Message to be sent Going to Channel Six Over Typical Example only !! On working channel, the calling station generally speaks first
The Distress Call Mayday, Mayday, Mayday Name of station in Distress This is Yacht Mise, Yacht Mise, Yacht Mise, Mayday, Position of Vessel in Distress My position is Fife Tree Zero Ate North, Zero, Six, Zero Won West Nature of Distress Vessel holed and sinking Two persons on board. Other Information Will fire flares, no further radio contact possible Mayday Typical Example only !! Send message on Ch 16 or any channel where a response is likely
When a Mayday is in progress only related radio traffic is allowed The ship in distress may impose control on the distress channel Normally a coastal radio station (MRCC or an MRSC) will assume control The ship in distress may impose silence -- SEELONCE MAYDAY A controlling station, which itself is not the vessel in distress can impose silence -- SEELONCE DISTRESS Radio silence is lifted with the words -- SEELONCE FEENEE If prudent use of the channel is required the word PRUDONCE is used Control of a Distress
Acknowledging a Distress Call Mayday, once only !! Yacht Mise Name of responding station This is Dublin Radio, Received, Mayday Typical Example only !! Any station hearing a MAYDAY must acknowledge, Wait for a brief moment to ensure that you are not over-transmitting a Coastal Radio Stationor a vessel nearer the scene If you are in a position to render assistance you must do so If the MAYDAY has been acknowledged, call the controlling station and advise them of your ETA and what assistance you can give If you can not respond, stay quiet, and listen Send a MAYDAY RELAY, See 13 a,b,c.
This is Yacht Mise, Yacht Mise, Yacht Mise, Mayday Relay, Mayday Relay, Mayday Relay Name of station Relaying Mayday Mayday Relay, Relay the original message making it clear that you yourself are not in distress Mayday Yacht Pogtone, Yacht Pogtone, Yacht Pogtone, position is (Position of Distressed vessel, not yours !!) Fife Tree Zero Ate North, Zero, Six, Zero Won West DistressMessage (do not add to it, just relay as it was received) Vessel holed and sinking Two persons on board. Will fire flares, no further radio contact possible This is Yacht Mise, Mayday Relay Repeat your name / call sign again at the end if the message is excessively long Typical Example only !!
Receiver Receiver 156.0 MHz 156.0 MHz Off when pressed Off when pressed Radio Wave Radio Wave On when pressed On when pressed Transmitter Transmitter 156.0 MHz 156.0 MHz Simplex Ch 0 Ch 0
Receiver 161.775 MHz Receiver 151.175 MHz 151.175 MHz Duplex Transmission Ch 83 Ch 83 Transmitter 161.775 MHz Transmitter Ship Station Shore Station
Typical Coast Station Receiver Transmitter Ch 16 Ch 16 Receiver Transmitter Ch 67 Ch 67 Receiver Transmitter Ch 83 Ch 83 Dublin Radio
999 Calls Malin Head Radio Malin MRSC Glen Head Radio Irish Marine Emergency Services Lifeboats Inshore All Weather IMES Coastal Rescue Units IMES SIKORSKI S61N Helicopter Air Corps Helicopters Belmullet Radio Dublin MRCC Dublin Radio Clifden Radio Wicklow Head Radio Shannon Radio Valentia MRSC Rosslare Radio Valentia Radio Mine Head Radio Cork Radio Bantry Radio
Other Relevant Developments • VHF channels can also be used to transmit coded signals which can “activate” the called station. • This is used to call emergency services on CH 67 • Channel 70 is reserved for Digital Selective Calling (DSC) and may not be used for voice transmission • DSC will required on all sets after 1999 to facilitate the new GMDSS service
Developments ... • GMDSS will include sattelite based distress communications via INMARSAT for ships in oceanic regions. • VHF DSC is required under GMDSS after 1999 • Electronic Position Indicating Radio Beacons (EPIRBS) are capable of automatically transmitting a combined distress and position signal. • Additional VHF direction finding equipment is currently being installed.
Revision • Licence Conditions • 1) Relevance of International Radio Regulations • 2) Relevance of Merchant Shipping (Safety Convention) Act 1952 • 3) Use limited to Maritime Mobile Service • Ships • Port Stations • Coastal Radio Stations • 4) Hygenic conditions • 5) Screening Lights and Safety of Operators • 6) Messages on behalf of Government
Revision ... • License Conditions Continued • 7) Operators Certificate of Competence • 8) Confidentiality of Traffic • 9) Obligation to Log all messages See General Regulations • 10) Payment for Coastal Radio Services • 11) Notification of Alterations to Equipment • 12) Right of Inspection • 13) Documents to be carried • Licence • ITC Radio (and Telegraphy) Regulations