| Most professional seafarers, given a choice of a single navigation tool, would probably prefer radar, even more than their chart plotter, gps, log, or echo sounder. it’s so versatile!
Most people probably think about buying radar because it can tell you where the ships are, but it can do a lot more than that: it can also tell you what they are doing, their course, speed, and closest point of approach. And it’s an incredibly powerful pilotage tool, capable of guiding you safely into harbour in fog or darkness, or out of an early morning coastal mist into clear daylight offshore.
No less important, in some respects, is that radar is perhaps the most “traditional” of navigation aids, in that it presents information, rather than answers, and does so in a form that requires a certain amount of skill and experience to use. Just like ribbing itself, developing and applying the necessary skill is a pleasure in itself. Radar, in other words, is fun!
JRC RADAR 1500 MK II £1051.63
Introduced a couple of years after the JRC1000, the display and operating procedures of the JRC 1500 are virtually identical to those of the R1000. Its scanner unit, however, is 50% bigger and a kilo heavier, and its transmitter output has been increased from 1.5kW to 2kW. The bigger antenna produces a more focused, more concentrated beam which, combined with the more powerful transmitter, should slightly increase the range at which targets can be detected, and is why the original version was, rather optimistically, marketed as a 24 mile radar.
Reducing the nominal range back to 16 miles for the Mk II is more a reflection of reality than a down-grading, but it’s pretty academic, anyway. Far more significant is that the bigger antenna improves the radar’s discrimination and picture quality even more than the bald figures given in the equipment specifications would suggest.
Our screen photographs show that the ferry which appeared to be over a mile long on the JRC 1000 had shrunk to little more than half the size, and a pier that was only vaguely discernible at a range of four miles on the JRC 1000, stood out very clearly on its bigger brother. If you were looking for a gap, such as a harbour entrance, it would show up on the 1500 at nearly twice the distance at which it becomes visible on the 1000.
£200 may seem a lot to pay for an extra six inches of scanner and another half kilowatt of power, but the end results are well worth it. The JRC 1500 has all the advantages of its little brother, it is easy to install, easy to use, uses about as much power as a couple of navigation lights, but thanks to the bigger scanner, it combines them with a picture that novices will find easier to use and that experienced users
FURUNO M1623 £1049
Furuno’s catalogue includes instruments, plotters, radios, and autopilots, but it’s at radars that the company excels, with a range that extends from deep-sea monsters with 28-inch displays and 12-foot, 30kW scanners, right down to the little 2.2kW M1623.
Even for the baby of the family, the installation instructions are slightly off-putting, as connecting the inter-unit cable involves taking the lid off the scanner and then removing a dozen fiddly little screws to get at the circuit boards inside, but the actual connection itself is no more complicated than snapping in a plug.
Its operating procedures are a similarly odd mix of the blindingly self-evident and the distinctly odd. It’s not at all obvious, for instance, that you have to press the <power> and <mode> keys in quick succession in order to switch from “stand-by” to “transmit”, or that switching the range and bearing markers on involves pressing the <mark> key, followed by either the <gain> or <alarm> buttons.
Setting it up for optimum performance, however, could hardly be simpler, with repeated presses of the <gain> button opening up mini-menus to deal with gain, sea clutter, and rain clutter in turn. In each case, the default setting is “auto”, so, with fully automatic tuning, it is quite possible to just switch the thing on and leave it to sort itself out. As usual, though, we were inclined to think that the fully-automated set-up tends to set the sea clutter control too high, and then winds the gain up too much to compensate. Switching it to manual was certainly worth the effort.
No radar nowadays would be regarded as complete without an array of features intended to enhance the picture, and the M1623 is no exception: it offers echo-stretch, off-centering, zoom, echo trails and even a variable scan speed.
These bells and whistles, however, don’t really do much for the M1623: it’s a small radar, with a big beamwidth and a not particularly high resolution screen, on which echo stretch is counterproductive and zoom are unlikely to be of great practical value. Features such as off-centering and variable scan speed are useful on high-speed boats, but the real strengths of the M1623 are that it’s a robust and simple radar, from a well-respected company, at a realistic price.
JRC RADAR 1000 MK II £851.88
Back in 1997, the Japan Radio Company introduced the R1000. They’d been making radars for Raytheon for years, but this was the first small radar to carry JRCs own logo, and the first to sell for less than £1000. Within a couple of years, street prices had fallen to less than £700, and they’ve bounced around at that level ever since.
Installation is easy: the scanner is supplied with its cable already connected, leaving just a simple plug-in connection to the display.
Operation, too, has been kept simple. The automatic tuning did a perfectly good job, and the Range, Sea Clutter, Rain Clutter, and Gain are all controlled by the same big twiddle knob: pressing it switches its function from one job to the next. That, however, isn’t all that can be achieved by this multi-purpose knob: pressing the <cont/dim> key turns it into a contrast and brilliance control, while pressing the <ebl/vrm> key gives it control over the bearing line and range marker.
The little joystick controls a cursor, giving simultaneous range and bearing measurements or, by pressing it reveals a menu of less important functions such as echo stretch, interference rejection, and a sectored guard zone.
In many respects, this is a lovely little radar: it’s compact, light, and an amazing price. It’s simple to install and simple to use, with few frills to confuse the first-time user. The one big let-down is that such a tiny scanner simply cannot produce a tightly-focussed radar beam. The consequence of this is that the picture looks blurred or blobby: a small buoy, for instance, stretches to a ten-degree smear, while a ferry that crossed our bows, four miles ahead appeared to be a mile long on the screen!
As an early warning device for crossing shipping lanes, or to confirm the proximity (or otherwise) of land, the JRC 1000 represents impressive value for money, but inexperienced users may find it difficult to interpret the picture while those with more know-how will find its value for serious radar plotting or blind pilotage is limited.
RAYMARINE C70
£1,600 INC VAT (INC SCANNER)
Raymarine has just celebrated 30 years in the marine electronics business. Originally called Nautech, it was best known for its Autohelm autopilots, but soon branched out into other electronic equipment before being taken over by the American Raytheon group in 1990. Ten years later, it was back under British ownership and renamed as Raymarine, with an innovative range of radars that allowed customers to team any display with any scanner.
This mix and match idea lives on and has been taken several steps further in the C and E series multifunction displays. Any of the five C and E series displays, by itself, is a colour chart plotter, but with a variety of add-ons, they can also turn into radars, fishfinders, or even (in the E-series) into video monitors! For most RIBs, though, the favourite option is likely to be the C70 display with a 2kW 18-inch scanner. Usually the C80 fits well in a RIB, and the C120 looks very good if there’s room on the pedestal.)
Installation isn’t quite as straightforward as some, because the cable isn’t pre-wired into the scanner. The most difficult bit, though is prising the top off the radome! Once you’ve managed that, the actual connection only involves pushing a multi-pin plug into its socket, and sticking the black and red power cores into their spring-loaded terminals. If your installation is likely to involve threading the cable through a tubular goal post or small holes, you may even find it easier than the JRC’s, because the scanner end of the cable is enclosed in in a tapered plastic shrink-wrap tube.
The display unit features an eclectic mix of push-buttons, soft keys, rocker switches and a press-and-twiddle knob, and the instruction manuals run to several hundred pages, so it looks pretty scary. In practice, though, it works very well: most of the really useful controls are activated by pressing one of the keys on the front panel, to reveal a group of options from which the specific control you want is selected by pressing one of the soft keys, and adjusted by using the cursor control pad.
Multiple VRMs and EBLs open the door to quite sophisticated blind pilotage and collision avoidance techniques, and if the radar is receiving heading information from a decent electronic compass, it’s capabilities multiply.
A sophisticated instrument, with plotting and pilotage capabilities that push the capabilities of a 6.5-inch screen and eighteen-inch scanner about as far as they can go, yet which remains easy to use.
FURUNO 1715 £1355
The family resemblance between the Furuno 1715 and the 1623 is so strong that comparing the two is a bit like one of those spot-the-difference-games. But everything about the 1715 is just a little bit bigger or better than on the smaller unit: the screen is 20mm bigger and the control panel has an extra couple of buttons; the scanner is 80mm wider to give a beam that is a degree more focused; and the nominal range has been increased to 24 miles.
Installation is very much the same as for its little brother, with the same total of fifteen screws to undo to remove the protective covers before you can plug the scanner cable into its circuit board! The operating procedures were immediately familiar from the 1623, too: the only noticeable difference is that the addition of a couple of extra buttons means that access to the EBL and VRM has been simplified and made more logical.
On the screen, however, the difference is much more pronounced. Increasing the diagonal measurement of the picture by 20mm increases its area by a useful 30% for a start. The real benefits, though, come from the scanner, whose narrower beam width yields a perceptible improvement in picture quality.
Other features that the 1715 share with its little brother include variable scan speed, by which the scanner’s speed of rotation can be almost doubled from its usual 24 rpm to over 40rpm, to refresh the picture more quickly when operating at very short ranges.
As with the two JRCs, the difference in price between the large and small Furuno models seems a lot for what you get. But if you’re buying a Furuno, you’re unlikely to be choosing on the basis of price alone, so it’s probably worth paying the extra for the 1715: it’s easier to use and very much more rewarding.
FRIED BRAIN, ANYONE?
We all know, from Doctor Who, Star Trek and the adventures of Superman and the Incredible Hulk that radiation is A Bad Thing. It makes you turn green, or glow in the dark, or something. Every day, it seems, planning committees around the country are presented with these incontrovertible scientific facts yet still they go on allowing evil empires to set up mobile phone masts in childrens’ playgrounds.
But surely the radiation that comes out of a radar must be even worse ... it will cook our brains, won’t it? Well, the answer is no.
There are two main threats posed by electromagnetic radiation. One is that it will affect the atomic structure of our bodies and cause cancer, the second is that it will cook us. In order to cause cancer, the radiation has to be at frequencies as high or higher than ultra-violet light. Radar waves aren’t, so they don’t. Radar waves are much closer in character to the microwaves used in a microwave cooker, so yes, they could cook us. But it takes time to cook something, even in a microwave, and time is something that a radar doesn’t have.
Radar doesn’t transmit continuously: it transmits, typically, for about a millionth of a second, and then switches to receive mode for about a thousandth of a second before it transmits again. So even while you are in the radar beam, you are only exposed to the eyeball and testicle-frying radiation for about 0.1% of the time. For the other 99.9% of it you are cooling down! And you’re only actually in the beam for about a sixtieth of the time anyway.
Overall, you are exposing yourself to more radiation hazard by using a hand-held VHF or mobile phone than by sitting right next to a small boat radar. Big ship
WHAT DO ALL THE KNOBS DO?
All small craft radars have the same main controls, though some may be automated, and others are often hidden in a menu control system.
Power On/Off: switches the power on and off
Standby/Transmit: switches the radar from its standby mode, in which it uses relatively little power, and in which its screen may be used to show data from other instruments, to its fully operational “Transmit” mode.
Brilliance and contrast: adjust the screen to make the picture as clear as possible under different lighting and viewing angles.
Gain: adjusts the sensitivity of the receiver to make weak contacts more visible or remove background “noise”.
Range: adjusts the scale of the radar picture, and changes the radar transmissions to suit the scale in use.
Tune: fine tunes the receiver to match the frequency produced by the transmitter. Optimum setting varies slightly, depending mainly on the temperature.
Other controls may be used to improve the picture, mainly by removing unwanted signals returned from waves or clouds.
Anti clutter (Sea): removes clutter found near the centre of a radar picture, caused by radar transmissions being reflected from waves. Excessive use can also hide real contacts at short range.
Anti-clutter (Rain): removes clutter caused by rain, hail, or clouds, found anywhere on the screen. Some radars have two rain clutter controls, one of which works only on the centre of the picture. It generally has little effect on most solid contacts, but can weaken the response from shelving coastlines. Used to excess, it can weaken all contacts.
Many sea schools and education authorities offer a one-day radar course that covers how to set up the controls, how to interpret the picture, and how to use the information for collision avoidance, navigation, and pilotage, Prices vary, but £80 is typical. Contact RYA Training (0845 3450400) for details.
CONCLUSION
On paper, the difference between the two JRCs, and between the two Furunos seem slight. But the pictures speak for themselves: whichever make you choose, you get much, much more by paying a little extra. Even in its most basic form, the Raymarine looks pricey by comparison but don’t forget it’s a multi-function unit, its performance is simply stunning and it comes complete with fish finder capability.
Tim Bartlett
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