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2018-02-14

I ♥ my new radar

She's a big 'un.
As the snowy weather, some welcome work and a minor surgical procedure have me sidelined this week, I thought to unbox the new Furuno 1815 4 KW radar I intend to bolt to Alchemy's mast in late April. The kids seem to like it.
Always good to know.
Furuno gear is as well-packed and organized as any higher-end Japanese gear I've encountered. The "important information" is undoubtedly online, but it's a nice touch to include the info in the box, because it would be HUGELY ANNOYING to get the radome up the mast, attach all the requisite wires and then get nothing, or the wrong thing.
Do NOT unwrap prior to installation.
The default power/data cable is 10 metres in length. This may well be enough to go two thirds up the mast, down to the deck and into the pilothouse, but I'm going to have the seller exchange this for a 15 metre length (it's coming in next week or so in another shipment) and I will hand this one over. I would rather have too much than too little cable; for instance should I for some reason wish to take the radar display aft to the outside helm, I'd use most of that 15 metre length.

There's a packing list and templates for each compartment in the 25 kilo box.
The chunkiest part, of course, is the 4 KW radome, which appears to be of the 19.2 inch form factor. The other model I was considering, the Furuno 1835, has a 24-inch dome that's heavier. The range is similar, however, and the power rating is identical. The difference between the radomes, for those of a technical bent, is as follows for the 1835: a horizontal beam width of 4.0 degrees and a vertical beam width of 20 degrees. The equivalent numbers for the unit I've purchased are 5.2 horizontal and 25 on the vertical. Both units work from 0.0625-36 NM in range, although the higher, the better, if you want that distance range. You may calculate your own potential range here.

These numbers break out in interesting ways: the higher the horizontal beam width, the lower the discernment or "sharpness" of the display. The vertical beam width, on the other hand, should be desirably high to account for the typical pitching of a sailboat at sea. The heeling, on the other hand, is dealt with by a self-levelling radar mount. I'm getting this one.

The main use for our radar will be twofold: seeing marine traffic on passage and seeing weather around us. I'm more interested in distance (hence the 4 KW radome, although the draw is reported as just 38 W) than I am in spotting a stick in the water a mile ahead. The nature of the sort of sailing we intend to do is largely high seas: radar buys you time. That said, this radar can be tuned to a pretty tight standard of seeing canoes and geese at 3 AM in the fog 1/2 NM ahead, should that be necessary. But I have seen radar used to steer between thunderheads and localized downpours, and I think this radar will excel at that.
I expect great things from you, radome.
There was no need to unwrap this radome prior to installation: this was just a check. 
Thorough, aren't they?
The 1835, which a few ocean folk have recommended to me, is a pretty sweet unit, but the 1815 debuted in 2017. It "paints" AIS targets more readily and has visual clues, such as "True Trail" mode, which visually suggest the speed and vector of objects of interest, such as radar targets that are also AIS targets.
The AIS info at the bottom of the cursored vessel is smoothly displayed with the radar return.
Rain and storm clouds and squall lines provide variable returns, although they are often gratifyingly tall enough to  be seen beyond the nominal distance limits of the radar. The same can be said of masthead-mounted AIS: it would not be ridiculous to "see" the AIS data of a fast-moving container ship at 50-60 NM given that its own antenna might be 60 metres off the surface of the water. AIS is also in the VHF band; certain atmospheric conditions can cause "skip" and multiply the occasional reception by several times. I once heard, for instance, the U.S. coastguard in Cleveland, OH in Toronto...on my handheld. It didn't last, but it was an example of skip. I wonder if an AIS target, ported to the radar display from my Vesper transceiver, would show up on the screen not as a "blip", but just as a contact on the lower half of the display? I'll enjoy playing with this, I can tell you. Someone else will have to sail!
It's possible to avoid a lot, but if you can't, it's good to have some warning of heavier weather approaching.
Above is the "weather" use of radar. The 1815 has a full manual mode, which, having fiddled with older radars and radios, I'm accustomed to using. I look forward to this as well, because I want to see if radar can spot certain phenomena, like "clear-air squalls", I've experienced at sea. Or maybe it was a microburst. Anyway, a bit of warning would have been nice, if that's possible.

The wires that go into the display. I have to run right-sized wiring to the display unit, but the draw is pretty low: 3.2 A
The plan is to have the display at the helm. While this unit is supposed to be either helm-mounted on a pivoting base, or flush-mounted into a nav station bulkhead, I am going to try to mount it on a strong armature from the pilothouse roof. That way, it can be tucked away and secured when not needed.
More fuses and covers and literature.
My plans to do this, however, might have to change if the radar display affects the helm compass, which is actually pretty accurate (locally, at least; it will almost certainly have to be swung in the Southern Hemisphere).
I was concerned this unit would be too small. My hands are large: I need not have worried.
The display unit itself is 8.4 inches top to bottom. That seems small, but I had a good look at it, as did Mrs. Alchemy, dragged over from her Boat Show gig as temp worker at a chandlery, and while there's a lot of information on the screen, it's easy to read. Again, this is most likely going into the pilothouse and will be closer to our eyes, should we wish, than the plotter will be, and it's only seven inches wide.
Sorry for the focus; I should've used the flash.
The back of the unit is pretty simple and robust. I'll post about it again after it's installed and running.
Oh, the places you'll go and you'll see their outlines first!
In the meantime, insurance survey time has come around again and there is much to do aboard prior to that expensive but necessary exercise.

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