Communications
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Communications
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COMMUNICATIONS: When we started sailing, back in the early '70's, communication equipment on small leisure craft were typically limited to a transistor radio to receive weather forecasts, probably a VHF transceiver and maybe a Radio-Direction Finder (a long-wave receiver equipped with a highly-directional antenna which allowed to determine the bearing of purpose-built Radio-Beacons). Only the large and wealthy yachts had short-wave radio tranceivers for long-range communication or devices like Meteo-Fax to be able to print weather charts. At the time the typical way to phone home was via a service provided over VHF radio through land stations that provided a connection to the telephone network; this service was also used by ships and therefore long waits were quite common, just to be able to talk to family at home for a few minutes. The same service could be accessed on short-wave, and was basically the only available means for communication while at sea. Nowadays technologies have greatly evolved and also the cost of on-board equipment has gone down significantly, making available to the leisure sailor several solutions that were previously unaffordable, as well as a range of new solutions. - VHF: Besides a general decrease of prices, the main evolution of VHF radio during the last years has been due to the introduction of GMDSS (Global Maritime Distress and Safety System) which defined the features of a range of devices useful for the safety of seafarers, such as the DSC (Digital Selective Calling) feature that allows any VHF radio to call and receive calls to and from a specific station, addressed by means of a station-specific identification number, the so-called MMSI (Maritime Mobile Service Identity), and to send automatically DISTRESS CALLS just at the press of a button; these calls include the identity of the calling station (its MMSI) and the position, provided to the radio via a connection with a GPS receiver. During our peregrinations around the world we had to acknowledge that the system is far from being universally used: quite many boats still have older radios that do not support DSC, and the result is that nearly NOBODY is using it to make calls, even land stations still make voice calls over channel 16 and only seldom use DSC.
The ICOM VHF transceiver which was installed on Shaula3, and (right) its remote-control microphone On Shaula3, in view of a challenging sailing, we opted for a top-of-the-range ICOM radio, which was also equipped with a very handy remote control/microphone which was installed on the steering pedestal in the cockpit (very convenient to communicate with ports during manoeuvres). Good radio on paper, but we suffered from lack of range (perhaps due to a faulty aerial?) and the cockpit microphone gradually fell to pieces due to lack of weather-sealing: pity, because it was really handy!
The Raymarine 260 radio installed on Shaula4 with its remote/microphone Despite these complaints, we would have happily installed another ICOM radio also on Shaula4, if it was not for an advert we saw about a new Raymarine set which featured a built-in AIS receiver: very interesting as it would spare us to have to install a separate AIS receiver and an antenna-splitter to connect AIS and VHF to the same antenna! ...and that was a bad decision, because only after having placed the order we discovered that the radio was so new that in fact it was not yet available for delivery!
Week after week of delays ensued, the departure date from Fiumicino was getting closer, and in the end we were forced to buy a "temporary" VHF radio! Obviously a cheap one, which would later serve as a spare, so we selected a Cobra, a brand we already knew. Low cost, but complete with all basic functionalities, including DSC, and very compact in size. ...and what about Raymarine? After several months of delays, the retailer gave up and offered us for the same price the Raymarine set WITHOUT AIS plus the AIS receiver and the Raymarine antenna splitter: exactly what we wanted to avoid! The message was clear though (no hope to get the right radio anytime soon!) so we gave up and in few days we got the stuff delivered. This new radio brought the concept of the microphone/remote
control to its extreme by not having a control dashboard at all: the radio is
just a black-box that can be installed out of sight, and up to 3 remote
microphones can be installed wherever convenient.
Interesting, we will have to see it in action to make a judgement. - HAND-HELD VHF: Already back in the '80's we bought an hand-held VHF set which
at the time was very handy mainly for two purposes:
With the advent of cell-phones the first need virtually disappeared (except perhaps in very remote areas without cell-phone coverage) and on Shaula3 the cockpit-mounted microphone was solving also the second. Having an hand-held VHF on board is anyway advisable, both for occasional uses such as communication between the boat and the dinghy and to carry it on the liferaft, just in case. On Shaula3 we had a small and relatively cheap ICOM radio, and we also kept an older ICOM we had since many years and that was stored in the emergency grab-bag. No special remarks to be done, besides the fact that neither one was waterproof, something that really sounds unbelievable for a portable device to be used on a small boat! For the time being on Shaula4 we bought only a cheap Cobra transceiver and we will evaluate the need to acquire a waterproof, GMDSS-compliant one in case of a major voyage.
- NAVTEX:
NAVTEX is another of the systems defined in the frame of GMDSS: basically it's a long-wave TELEX receiver. Dedicated earth stations, located several hundred kilometres apart, broadcast all kind of information such as Notices to Mariners, military exercise areas, dangers of any sort and, most importantly, WEATHER FORECASTS. Sure, many of these information are also broadcast in voice on VHF and short/medium wave radio, but besides the possible reception or language problems of a voice transmission, there is always the risk of everybody being busy with something else just at the time of transmission! NAVTEX does all automatically, and you can recall the messages on screen at any time: practical, simple, you can read the messages as many times as you wish and perhaps copy them on paper or even transfer them to a PC. There are essentially two types of Navtex receiver: with or without a display: those without are intended for use connected to a PC and therefore make sense on boats where a PC (or a Tablet) is used for navigation and is permanently on. We preferred a model with its own display, and in this category the undisputed winner is the Furuno NX300: a very sensitive receiver, and very simple operation. We had one both on Shaula3 and on Shaula4 and never had any complaint. - METEO-FAX: Despite being an obsolete technology, meteo-fax could still be an interesting solution to receive meteorological charts on a small boat, if it wasn't for some limitations: - broadcasts are at fixed times and each chart lasts several
minutes, so we go back to the problem of being free from other tasks at the time
of transmission, or to have an (expensive) automatic receiver On Shaula3 we had the possibility to receive Meteo-Fax transmissions on the PC, taking advantage of the SSB radio's PACTOR modem that could be used as a demodulator, but apart from few tests, we never used it in real life! Too complex, and in the end it was much easier to get GRIB files by e-mail. - SSB/HF RADIO: Despite being another obsolescent technology, short/medium wave SSB radio still has a place on offshore vessels and also seafaring yachts. On Shaula3 we had no choice: an SSB radio was a mandatory requirement of the Blue Water Rally, and in fact twice every day all the fleet was communicating its status and position over the radio.
The small console of the SAILOR SSB radio... ...and the actual huge transceiver unit installed in a locker Most boats in the fleet opted for ICOM M801 or M802 radios
(the first being the European version and the second for the USA market) but due
to mysterious type-approval issues in Italy we could not do the same and were forced to
adopt a radio by danish firm Sailor. Once the big expenditure for the SSB radio was done, it was obvious to spend a little more and get also a PACTOR MODEM, a special modem that allows low-speed data transmission over the SSB connected to dedicated earth-stations. We chose the "Sailmail" service, a low-cost volunteer-based service specifically aimed at sailors and which is covering nearly the whole world. There are also some commercial services (among them Monaco and Kiel radios) which are supposed to be of better quality. For the time being we do not plan installing an SSB radio on Shaula4, considering that we are not planning the kind of voyage that would justify the cost.
The SONY multi-band receiver that we found installed on Shaula3 The simple multi-band receiver by NASA Still, a multi-band RECEIVER would be useful: for the time being we rely on the trusty old SONY that we found on Shaula3 (where we used it very little, as there was the Sailor SSB better serving the same needs); in case we will feel like equipping ourselves with a dedicated nautical receiver we will probably opt for the simple radio manufactured by NASA or for an amateur radio. - CELL-PHONE (GSM): In the frame of about 20 years GSM cell-phones have become ubiquitous, we got a signal almost everywhere except few remote islands, and practically everywhere it was possible to buy cheap local SIM-cards or sometimes even telephone sets. Despite the metal hull, we never had problems connecting while near land; we never felt the need to install a fixed external aerial. Broadly speaking, the telephone sets may well be the same that are used at home, with a few caveats: - make sure the phone set is 4-band: this is needed only in
few places around the world, many of which are in the Carribbean; not a big
problem, many sets on the market have this feature. - USB DONGLE/INTERNET ACCESS POINT: When we left for the circumnavigation with Shaula3 it was still common practice to use a GSM phone as a modem to perform a low-speed ("dial-up") data connection, but by the time we came back the situation had changed, with the advent of 3G and 4G networks and the use of USB dongles to perform high speed data connections. USB dongles, although low-priced and easily found, have the
drawback of serving just one device, typically a PC, and of not being usable at
all with Tablets and Smart-phones (which may be able to connect on their own, but
require a dedicated SIM-card). The cost is reasonable, usually under 100 Euros, and many smartphones have the same capability built-in (but make sure that your subscription allows you to use this service: many low-volume subscriptions do not!). Quite obviously we equipped Shaula4 with one of these 4G access points which would give us data services near shore; we also kept a special long-distance wi-fi interface that would allow to connect a PC to local wi-fi networks, which often are weak or far from the boat as we often experienced during our voyage. - PC/TABLET:
We learned the hard way that PC's are exposed to damage aboard a small boat and having a spare, already loaded with software applications, is very advisable; therefore, rather than having an expensive PC, as we did on Shaula3, it's better to have two, or even three cheap ones, preferably identical and with the same Sw, as we did for Shaula4. The same universal 12V power units have served us well on Shaula3 and later on Shaula4 to feed the PC's when away from shorepower; at the time they were hard to find, but now not anymore.
- MULTI-FUNCTION PRINTER:
On Shaula3 during the circumnavigation we even carried a multi-function printer (that is, one that can also be used as a scanner or a photocopier); the cost is minor, and the possibility of printing documents or, occasionally a photo to be given to somebody, is very handy. In many places authorities require an inordinate number of copies of the ship's papers, which we could reprint at any time from the scans we had prepared before departure and stored on the on-board PC. Although we did carry some spare ink cartridges, after a while
we ran very short on them because buying them along the voyage turned out to be
not so easy: our model was marketed only in Europe, and it was totally unknown
in the other continents!
- SATELLITE PHONE:
Just few miles from shore, and even in the Mediterranean you are out of cell-phone and VHF-station coverage. During a short passage this may be acceptable but on ocean passages a solution must be found to be able to communicate and possibly send/receive e-mail (including weather bulletins). Traditionally these needs used to be fulfilled by SSB radio but nowadays sat-phones have become an easy and cost-effective solution, both based on general purpose (Iridium, Thuraya, Globalsat) as well as on maritime-specific services (Inmarsat). On Shaula3 we had two Iridium sat-phones with the dedicated
data-kit: one of the two sets followed us on Shaula4, where we will use it in
case of a long voyage which would justify the cost of a subscription
(unfortunately Iridium does not encourage low-volume/short duration
subscriptions). - AIS:
AIS (Automatic Identification System) is another of the GMDSS components, mandatory aboard ships and fishing boats above a certain size: in few words, an AIS-equipped vessel broadcasts its name, course, speed and other data on a dedicated VHF channel. AIS receivers display this information on a dedicated screen or can send the info to the radar/chartplotter screen. Its to some extent a duplicate of radar: on one side, it can confirm and integrate the info coming from radar and MARPA, but it must be remembered that not all vessels out there have an AIS transmitter, so what you see on the screen may not be the full picture! At the time of Shaula3 departure AIS was just beginning to be available to small craft, and our chartplotter was not compatible so we could only have installed a stand-alone device like the one pictured on the right. On Shaula4 we rather opted for a receiver integrated in the Raymarine instrument chain. Only a receiver and not a transmitter: the price difference
was important, maybe we will reconsider in the future... Continue reading at the page concerning Entertainment devices
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Webmaster: Gianfranco Balducci - email: gfbalduc@tin.it Last Update: 07/09/2017
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Although we do not have a PC- or Tablet-based navigation
system, a PC or a Tablet is essential to be able to send and receive e-mail,
download weather charts or GRIB files, update our blog or web-site, and also to
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