The ship has a license and a unique call sign which is usually programmed into your VHF set. To operate the set, someone on board must have a short range operators certificate. See "Red Tape" for further information on this.
In the UK the set usually selects channel 16 automatically when switched on which is the international distress channel. There is usually a dedicated channel 16 hot button so it is obvious what channel to select in an emergency. On VHF (called here "Marifon") sets on European inland waterways, the emergency channel is not normally needed so the intership channel 10 replaces the channel 16 hot key and this is the channel you normally monitor.
When you approach a bridge or a lock, if they are equipped with VHF, you will see a sign giving the channel to communicate. In some instances we have found that a lock keeper can be responsible for a lift bridge miles away from his lock and he must drive to the bridge to open it. Without VHF you might be faced with a long walk to request the bridge be opened!
Language can also be a problem if you do not speak the local lingo! They will just ignore your communication if they do not understand you, as will the big barge skipper who chooses not to understand when you ask him to slow down!
In order to satisfy new EU regulations we purchased a second VHF radio, this one is portable. The regulations require vessels over 20m LOA to have two radios, one to transmit and one to receive. The transmitter must be equipped with ATIS (Automatic Transmitter Identification System) which identifies the ship. The new radio must be programmed with the vessels unique ATIS number. Unfortunately the UK has not recognised this new ATIS system which is administered by a a bunch of countries called RAINWAT (Regional Arrangement concerning the Radiotelephone Service on Inland Waterways commitee) states so OFCOM (the UK Office of Communications) advised us to contact the local Belgian authorities for advice. The advice was to use our MMSI (Maritime Mobile Service Identity) number prefixed by a 9. This is allocated by OFCOM for DSC (Digital Selective Calling) radios, a system not unlike ATIS which identifies the vessel but can also be linked into your GPS navigator to give the ships position. It is intended mainly for distress calls at sea. Our ATIS portable radio is not a DSC set so OFCOM said they could not issue an MMSI number for it! Catch 22 I think! The matter was eventually resolved as a stop gap measure by OFCOM issuing a NoV (notice of variation) to the ships radio license providing us with an MMSI number and an ATIS number (the MMSI number prefixed with a 9). The covering letter is hedged with "what me Guv" phrases, the gist of it all being as follows:
One of the main obstacles, the formulation of the ATIS number by prefixing the MMSI number with the digit 9, has been resolved but many other issues remain:
1) There is no harmonised examination syllabus.
2) A copy of the RAINWAT arrangement must be kept on board but there is no official translation in English.
3) Radios must be able to switch between ATIS and DSC but there is no agreed standard and no UK interface requirement for such equipment.
4) There are other technical , practical and legal difficulties.
OFCOM say that UK vessels may encounter problems in RAINWAT states who may not recognise UK paperwork concerning ATIS so although the NoV satisfies UK law they can not guarantee it will satisfy other countries.
The portable set must only be used on the vessel that the NoV refers. It must not be used within 14 miles of the UK or Channel Islands coasts.
While you are on the inland waterways of any RAINWAT state you will be subject to their jurisdiction.
They conclude by saying that this NoV is not yet generally available so it seems that they have made a special case to shut me up!!
We now come to a navigational aid but one which uses VHF which is called AIS. In August 2012 we will install a class A AIS (Automatic Identification System) transponder and upgrade our computer memory to 4Gb RAM so it can run PC-Navigo 2012 with AIS and ENC (Electronic Navigation Charts) charts. Most commercial vessels are now fitted with this system which greatly reduces the possibility of collision. The AIS transponder broadcasts your exact position and speed using a VHF transmitter from a GPS signal and if you are blue boarding, etc. together with your size and dimensions which are programmed into the transponder. You can see any other ships details which also have AIS installed in graphical form on the ENC chart on the computer screen up to several kilometres distant. AIS is already a requirement in the ports of Antwerp, Gent and Rotterdam, on the Rhine and Danube and will eventually become a navigational requirement for all vessels, certainly on the busy commercial canals and rivers.
There is a misconception that VHF signals can only be received if the transmitter is in line of sight. With UHF this is certainly true but the longer VHF wavelengths can dodge and bounce off obstructions between transmitter and receiver which means you can often receive signals around several bends of a river, very handy to be able to see some big ship coming round a corner blue boarding on the wrong side of the river! Lock keepers will also have the ability to see this vessel information so they can fill up their lock knowing each vessels dimensions and skippers can see the names and nationality of approaching ships should they need to contact them by radio to advise them of their navigational intentions.
It is only an aid to navigation however and the danger is that we come to rely on it until one day a big ship appears round the corner whose AIS is defective or not switched on or the vhf signal obstructed and you couldn't see him and are going too fast to stop!!