NCI Product 2

Coastwatch Portland Bill does not transmit on VHF Radio but there may be circumstances when due to operational difficulties Portland Coastguard may request us to transmit and receive. In order to meet this eventuality all Watchkeepers will be required to be trained in the Transmitting Rules on maritime Frequencies.

The Watchkeeper must constantly monitor the VHF Radio for vessels in distress and weather information especially Gale warnings. It is therefore mandatory that Watchkeepers monitor channels 16 and 10.

This channel is exclusively for the rescue services i.e. Life Boat and Search and Rescue ( SAR ) Helicopter.

The shipping forecast consisting of Gale Warnings, General Weather Synopsis ( High / Low pressures and which way they are expected to move). Along with Area Forecasts and Coastal Reports are broadcasted on this channel. All scheduled broadcasts are announced on CHANNEL 16 with the request to switch to this channel.

This Channel is constantly monitored by HMCG ( Her Majesty Coastguard ) for Distress signals, Merchant vessels travelling East to West through the separation zone voluntarily report to HMCG. They will initially transmit on CHANNEL 16 and then be asked for routine traffic go to Channel 69 or 67 where the information will be exchanged.

Routine traffic between small vessels and HMCG is carried out on this Channel. Initial contact between the vessel and HMCG is on CHANNEL 16 with HMCG requesting the vessel to go to this Channel.

Routine traffic between large vessels and HMCG is carried out on this Channel. Initial contact between the vessel and HMCG is on CHANNEL 16 with HMCG requesting the vessel to go to this Channel.

While Digital Selective Calling (DSC) is one of the most important parts of GMDSS, it is the last to be fully implemented. DSC provides a means of automating all day-to-day marine terrestrial calling - making marine radio as easy to use as a telephone. DSC effectively provides the operator with a digital dialling system capable of ringing an alarm at a distant radio station when a call is addressed to that station.

Like a telephone, you do not need to know how the call has been routed or even the frequency or channel being used. All you need is a means of alerting the other party by calling their number, and then a means of talking to them. Under GMDSS, all vessels are allocated a unique Maritime Mobile Service Identity (MMSI), which is a unique nine digit code. The digital calling information is transmitted on specially designated channels. In the case of a VHF radio, this is Channel 70. Channel 70 is dedicated for DSC use and must under no circumstances be used for anything else.

An added benefit of DSC is that the digital dialling signal can also carry other information, such as your vessel’s identity, position and the nature of the call as well as information specifying the channel upon which subsequent communication should take place. The entire message is transmitted in one quick burst, thus reducing the demand time on the calling channel.

In a distress situation, all necessary information can be sent automatically at the touch of a single button. The vessel’s position can be determined from a GPS navigation receiver connected to the radio or entered manually. Its identity is permanently coded into the radio in the form of the allocated vessels MMSI number. The nature of distress can also be selected by the operator if there is time to do so.

Using digital coding, DSC automates all the radio functions with which existing marine operators are familiar. It also relieves the person at the other end from the tedious task of manual watch keeping. All the old familiar functions are still in place, but they now have English names and are accessible at the touch of a button.

In an AIS network, each vessel has its own on board GPS system, which provides the

position, course and speed of the vessel. This is linked (or in many cases, integral with) a

radio transceiver. This has three receive channels (AIS1, AIS2 and DSC channel 70) but only

one transmitter (which can transmit on any of the channels). The two radio channels are split

up into time slots of 26ms each, so that there are 2550 slots in every minute. When an AIS

unit first switches on, the first thing it does is listen to the AIS channels for any existing vessels

that may be transmitting. From the traffic on these channels it builds up a map of the activity

on each channel so that it can then chose a time to transmit when the channel is likely to be

quiet. Once it has chosen a time slot in which to transmit its message, it also sends a

message to reserve a slot in the next frame so that other ships will not transmit at the same

time as it. Each vessel will report its position, speed and course at a defined rate depending

Introducing the first weather station in its price range to use frequency hopping spread spectrum radio to transmit and receive data up to 1000' (300 m) line of sight. That's over three football fields in length—and three times farther than competing stations!

Our Vantage Pro2 still offers the same great features of Vantage Pro such as forecasting, on-screen graphing, and much more. Quick view icons show the forecast at a glance—sunny, partly sunny, cloudy, rain or snow—while a moving ticker-tape display gives more details.

Our integrated sensor suite combines our rain collector, temperature and humidity sensors, and anemometer into one package—making setup easier than ever and improving performance and reliability.

For improved accuracy, temperature and humidity sensors are housed inside a radiation shield. The shield protects against solar radiation and other sources of radiated and reflected heat. Choose our standard radiation shield, or, for the utmost in accuracy, our fan-aspirated radiation shield. Available in both wireless and cabled versions. For more details.

NAVTEX is a system for the broadcast and automatic reception of maritime safety and weather information. NAVTEX provides shipping with navigational and meteorological warnings and urgent information through either on screen display or automatic printouts from a dedicated receiver. NAVTEX is a component of the IMO/IHO Worldwide Navigational Warning Service (WWNWS) defined by the IMO. It has also been included as an element of the Global Maritime Distress and Safety System (GMDSS).

NAVTEX transmissions are sent from localised transmitting stations situated worldwide. The power of each transmission is regulated so as to avoid the possibility of interference between transmitters. Users can set their NAVTEX receivers to receive specific message types and reject others. Messages such as navigational and meteorological warnings and search and rescue information are non-rejectable to ensure that ships equipped with NAVTEX always receive the most vital information. Users can choose to receive information from the single transmitter that serves the sea area around their position, or from a number of transmitters. 18

NAV6plus

Simultaneous dual channel NAVTEX receiver with large, easy to read LCD screen.

The NAV6plus offers simultaneous dual channel reception as standard. Information is presented on a large and easy to read LCD display, rivalling paper print-out for legibility. With navigation space becoming increasingly restricted in modern boats, the ICS NAV6plus display concentrates NAVTEX and critical NMEA data from your GOS or instrument diaply, into one central point. An electronic log book is updated at regular intervals and can be printed out later via an optional printer. NAVTEX is part of the Global Maritime Distress and Safety System (GMDSS). It broadcasts weather and navigation warnings, in English on 518kHz every 4 hours from transmitters all around the world. Increasingly, local language and small craft information is also transmitted on 490 kHz. The ICS NAV6plus can monitor both channels simultaneously.

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We have a very powerful pair of binoculars which we have mounted on a ceiling rail which gives us a 270° view. It allows us to get right in and take the information straight from vessels to log down when they go past our lookout.

There is no doubt that compass binoculars have become very popular for marine use. The early types were not always successful as some of the compasses were not very satisfactory but in the past few years there are been vast improvements in the compasses incorporated. There is no doubt that when looking through binoculars for a buoy or marker being able to take a bearing at the same time makes practical sense. If a separate hand-bearing compass is used there will be times when you are unable to locate your object without the aid of binoculars. This is especially true in dull light condition when a good 7x50 will enable you to see more than the naked eye.

Some people may find that it takes a little while to get used to using compass binoculars. The compass scale will appear in the top or lower quarter of one of the lenses as you look through them and the trick is to practice looking straight ahead at your object through the binoculars and read the compass bearing at the same time, rather than looking down at the compass scale and up again at the object. Taking a mean average of the readings will produce a remarkable degree of accuracy at sea.

We also have various other equipment to hand if and when we need to, to aid us in our day to day monitoring of the waters around the Portland Bill Area.