Radar Recommendation

[capecuddy]

Folks, you need to be checking out the tremendously simple and effective operation of the 3G and BR24 broadband radars from Lowrance and Simrad, both Navico companies.

Very high range resolution (1 meter)....safe as a cell phone RF hazard-wise...minimum range allowing you to see targets literally 30 feet off your gunwales. When used with a heading sensor (like Simrad RC42), can be overlayed on your GPS chartplotter charts along with your GPS position. When you scale your chart, you scale your radar accordingly. Operates very well automatically and offers sensible adjustments for sea clutter, rain clutter and more esoteric adjustments for the not-so-faint-of-heart.

They integrate with Lowrance, Simrad and Northstar systems easily....not sure of others.

Retired after 41 years in defense electronics (mostly big radars) and these broadband radars are the coolest radar technology I've seen out there. They don't solve every radar problem. You aren't going to use them to spot birds for fishing spots unless you don't want to use your binoculars. They don't see ships out past 8-10 miles real well, but then again a ship 8-10 miles away is not likely to run you over real soon. But boy do they help you nav in tight quarters in darkness and fog.

[Jon Hacking]

Does anyone have actual experience with these "broadband" radars? They're actually "FM" radars as their "broad" band is only 75MHz between 9.3-9.4GHz. I like their instant-on, but they can't get much reflection when they're only putting out 165mW. So what's their real usable range??

CapeCuddy says "They don't see ships out past 8-10 miles real well" but my experience with my 16nm JRC pulse radar is that it never saw more than 8nm. Everyone knows that spec-writers lie like dogs, so I'm trying to find the REAL range that I'll likely see, say, a 30' fishing boat at.

Any real experience with these units (Lowrance or Simrad) much appreciated!

[capecuddy]

Originally Posted by Jon Hacking

Does anyone have actual experience with these "broadband" radars? They're actually "FM" radars as their "broad" band is only 75MHz between 9.3-9.4GHz. I like their instant-on, but they can't get much reflection when they're only putting out 165mW. So what's their real usable range??

CapeCuddy says "They don't see ships out past 8-10 miles real well" but my experience with my 16nm JRC pulse radar is that it never saw more than 8nm. Everyone knows that spec-writers lie like dogs, so I'm trying to find the REAL range that I'll likely see, say, a 30' fishing boat at.

Any real experience with these units (Lowrance or Simrad) much appreciated!

I have 160 hours on my 3G.

FM/CWI uses pulse compression to create signal processing gain, high range resolution and excellent separation of clutter types. That's how it done with low peak power. The broadband radars are transmitting essentially all the time instead of for a few microseconds at high peak power. The broadband radars use techniques very similar to some of the best military fire control radars.

I my experience, I could see tankers and freighters at 10+ miles. Fishing boats (commercial) to around 4 to 5 miles and fiberglass boats at 2.5 to 3 miles.

The broadband radars are a different kind of radar. They can see small targets within 20 ft of your bowrails. At the head of a channel, I can see both small aton's (a nun/can pair) on port/stbd sides as I go thru the pair. I can see my own wake as sea clutter at the back of my own ship symbol on chart overlay.

If something can hit you within 3 minutes, you can see it well.

It is not great at finding birds at a range that will help your fishing.

It is awesome for close navigation, especially when used in conjunction with a heading sensor doing chart overlay. Very accurate. Land clutter shown on chart more accurately than most charts of inland waterways. Exposed shoals shown accurately offshore.

My 3G brought me home thru 10 miles of complex shallow waters (Chatham, MA) and 50 markers with no spotlight in new moon darkness twice. I could see the difference between my personal waypoints for markers and the actual position by radar to avoid hitting the channel markers. I could see the markers on radar as I spotted them visually as I passed, using my rear deck lights.

Hope that helps.

[Jon Hacking]

Thanks - excellent info. We're a blue-water cruiser (currently in Thailand) so very interested in your detection ranges for various types of boats - thank you. How far away do you see land?

We are also interested in the 3G. How is its weather (squall) tracking? How far away can you see squalls? Can you see holes between the squalls in a squall line?

Also, I understand the 3G (or possibly the MFD display) has MARPA capability. Have you tried it? Does it work? Does it add anything to our AIS on OpenCPN?

We've always used OpenCPN or similar nav program, so never needed a chart plotter (& never wanted to buy all those chart chips). It seems very $$ to buy a MFD just to display my radar, but I guess there's no option. The NSS touch-screen units look easy to use (& "only" $1500). What display do you use? What would you use if you had to do it over?

Cheers!

[capecuddy]

Originally Posted by Jon Hacking

Thanks - excellent info. We're a blue-water cruiser (currently in Thailand) so very interested in your detection ranges for various types of boats - thank you. How far away do you see land?

We are also interested in the 3G. How is its weather (squall) tracking? How far away can you see squalls? Can you see holes between the squalls in a squall line?

Also, I understand the 3G (or possibly the MFD display) has MARPA capability. Have you tried it? Does it work? Does it add anything to our AIS on OpenCPN?

We've always used OpenCPN or similar nav program, so never needed a chart plotter (& never wanted to buy all those chart chips). It seems very $$ to buy a MFD just to display my radar, but I guess there's no option. The NSS touch-screen units look easy to use (& "only" $1500). What display do you use? What would you use if you had to do it over?

Cheers!

I use sirius weather overlay and don't usually go out in storms, so I have limited experience withnweather, though have heard others comment favorably.

I bought the RI10 interface thing but my installer failed to connect the N2K interface, so never got MARPA checked out this season...on the winter to do list.

When I commented about tankers and freighters at 10 miles, I usually had the radar paint striping thru the AIS symbol from my Standard Horizon GX-2150.

I use the Lowrance HDS-10. If I could have stood another month is boat delivery, I would've gone with a Simrad NSS-12.
I would say I see land clutter around 5 miles.

I think if my use was primarily offshore, I might consider an alternative to the broadband radars. Or have both. You can only run one at a time as they are in the same band. Open Arrays work really well especially for finding birds.

Chart overlay really work well with the 3G since it auto ranges to the scale you are running the chartplotter at.

[downunder]

Originally Posted by capecuddy

I think if my use was primarily offshore, I might consider an alternative to the broadband radars. Or have both.

This is an interesting comment as I like to use radar for coastal navigation (plotting on Chart) and a good range is important.

[ChannelIslander]

Originally Posted by Jon Hacking

We've always used OpenCPN or similar nav program, so never needed a chart plotter (& never wanted to buy all those chart chips). It seems very $$ to buy a MFD just to display my radar, but I guess there's no option.

Jon,

Have you considered direct-to-PC radars such as the ones from Pegasus in the UK?

[Moufflon]

Hi Jon

Can you point me to: direct-to-PC radars such as the ones from Pegasus in the UK

RGS///Pete

[Jon Hacking]

Originally Posted by ChannelIslander

Jon, Have you considered direct-to-PC radars such as the ones from Pegasus in the UK?

No, I didn't know such things were available. Can you post a pointer? What do they cost? How well do they work?

Thanks!

[Dockhead]

Originally Posted by downunder

This is an interesting comment as I like to use radar for coastal navigation (plotting on Chart) and a good range is important.

The broadband radars were tested recently by Yachting Monthly. They got reliable returns from anchored ships at 12 miles with the new 4G broadband radar; somewhat less with the 3G. I guess an anchored ship would correspond to fairly subtle coastal features. Is 12 miles to see details on the coast enough for you?

It certainly is enough range for me. At 12 miles or greater I am quite happy to trust my chart plotter. Within a few miles of something, and especially in bad visibility, it is great to be able to check the chart against radar.

From what I have heard, the broadband radar does a fairly poor job showing weather systems. A downside I can accept, but others may have a different agenda.

[Dockhead]

Originally Posted by Jon Hacking

No, I didn't know such things were available. Can you post a pointer? What do they cost? How well do they work?

Thanks!

Nobeltec also make a direct-to-pc radar.

[mikereed100]

Originally Posted by Dockhead

Nobeltec also make a direct-to-pc radar.

I was pretty exited to read this until I saw the prices. IR2 17" radome over $3000 and the software around $900. Yow!

[S/V Alchemy]

Originally Posted by Tim Schaaf

Until a very few years ago, when Raymarine introduced their digital radars, they had a potentially lethal fault. I brought this to the attention of their VP, who put me in touch with their top radar guy, who acknowledged it. But, this fault never has made its way into any user warnings that I have heard of. They also said other non-digital radars suffered from the same thing, and that the digital ones don't, but I can't confirm that.

What happened? Although I had used other radars for years (did a lot of singlehanding for over twenty years, and a radar alarm was my "other" crewmember), I always tuned them manually, like I was trained to do. The manual for the Raymarine Unit I bought (new) in 2004 dealt with manual tuning, gain, sea clutter, etc, very offhandedly, and was strongly oriented toward the automatic controls. I realize now, that this was probably a marketing ploy. Anyway, I tested the auto controls, and it was obvious that the radar tunes itself automatically with great accuracy. I could not do better myself. The same was not true of either the gain or the sea clutter controls, but it could take several minutes for this to manifest itself. Manual radar controls usually have levels defined by numbers, which, on my set, were from 0 to 100. On my set, the best gain (tuned for a light background speckle) is somewhere from 76 to 82, depending upon the range setting). Sea clutter would be optimized somewhere between 0 and 30, depending almost entirely upon sea state. Auto controls started on the same range, but it was only a year or so later, when I started getting very suspicious of some missed targets, that I realized that, over a few minutes, gain would settle down to around 50 - 55, which would effectively erase lots of boats, buoys and the occasional island. Yes, island. The automatic Sea Clutter controls were better, but contributed further to degrading targets. In my opinion, it was highly irresponsible of Raymarine to include such a flawed "automatic" system, with the strong implication that the auto setting was all you needed to use. Silly me, I thought that my old training had been superceded by a true improvement in technology.

The aforementioned tech's answer when I asked him about this was. "Sure, all radars, pre-digital, have this fault. I would never use auto settings in any situation where the performance of the radar was important!" How could they sell such a feature?

This was driven home to me in a big way before I discovered this flaw. Some of you may remember either hearing or reading of a catamaran in the Caribbean 1500, 2004 edition, that collided with a NOAA weather buoy about 220 miles off Cape Haterras. It was written up in water sailing">Blue Water Sailing and Latitude 38, among other places, and there was a fair amount of online chatter about the skipper who must not have been on watch to make such a mistake. Well, that guy was me, and I was on watch, at the wheel, looking out ahead on a pitch black night, well aware that there was a six meter, in diameter, weather buoy out there somewhere, supposedly with a light flashing every 20 seconds. And, I had my radar on for precisely this reason and, no, I was not singlehanding. The situation was complicated by the fact that the buoy is anchored in 12,000 feet of water, so its swinging circle was several miles in radius.

Since I had three other crew on board, none with extensive radar experience, I had made the mistake of telling them to just set things on automatic. I had come on watch about a half hour before the collision, and probably had not thought to re-tune manually. I did not think I needed to. Unfortunately, it also turned out that the light that was supposed to flash every 20 seconds was out, which I am told is highly unlikely as there are several back up lights set up to flash if the one higher up the line fails. Well, I suppose that salt water is an issue with the electrical systems on buoys, too, because, all the lights were out, which we confirmed after the collision.

Despite the fact that I was looking straight ahead, I did not see the yellow 6 meter in diameter buoy (it is more like a huge floating hockey puck with various sensors and antennae) until our nav lights flashed on its reflective tape, about a boat length and a half dead ahead. We were doing seven plus knots, under autopilot. The Raymarine 7000 autopilot control head is not backlit, and I had only owned the boat for a few months, so I did not know, instinctively, which button was "standbye"; in the instant before impact, I just leaned as hard as I could on the helm, and managed to avoid hitting the buoy dead on, but caught it on the bow on the port hull. This opened a hole right on the stem about two feet measured vertically. That is when I learned how tough a Leopard 45 is ( it would have done much greater damage to most other boats) and how effective the water tight bulkhead is.

Very long story short, (and glossing over the un-requested mayday sent out on our behalf by another boat in the rally, which resulted in attention from a C-130, two USCG cutters, and a helicopter), we did make it back to the Chesapeake with a huge hole but no water into the hull aft of the collision bulkhead. And, after a $37,000 insurance claim and many months of a charter season lost, we were back in business.

For a couple of years, I wracked my brains as to how I could have missed such a buoy on the radar. And, believe me, I was asked about it to no end, as well. My friends, who knew of my singlehanded past and years of radar dependency were particularly incredulous. It was a long time until I finally put two and two together, in a manner that was easily replicated. Quite simply, the automatic settings had blinded the radar, and I was not aware of it. And, I had not bothered to re-tune manually.

We were lucky. No one was hurt, and the boat was repaired. But, how such an "advanced feature" could make its way out of a responsible factory, I do not know.
It is probably true that all older radars share this flaw. Certainly, the old maxim was to always use manual controls. But the manual sure suggests otherwise, and I would be willing to bet that the vast majority of radar users on this forum probably use the automatic controls. And, apparently, this is OK on the digital sets, although I would test very carefully before I would feel comfortable.

But, getting back to the OP, if you get a radar more than a few years old, be sure to learn how to set your controls manually. You will be just fine, if you do. My Raymarine works very nicely that way. As have all the other radars I used previously. Just take the instructions for the automatic settings with a grain of salt.

Cheers,
Tim

What a great and informative story, which I missed the first time around and have quoted in full in the hopes someone else will learn as much from it as I have.

I have "played" mostly with a friend's old Kodan CRT model, and just like some of my old radios with BFO controls, they are sensitive, tweakable things. It is amazing what a reasonably informed sailor can discover playing with the knobs on both an older radar and even the newer models. I once had a guy make an island "disappear" while the boats in front of it became more well-painted. Other uses of course include losing the boats, but getting well-defined blobs of bands of rain, which can guide you nicely at night.

RADAR is a great tool, but it will never be a simple one, and all users of it should really have enough understanding to work it actively, rather than through the passive application of automatic tuning options.

[S/V Alchemy]

Originally Posted by downunder

This is an interesting comment as I like to use radar for coastal navigation (plotting on Chart) and a good range is important.

I have heard similar comments from electronics installers. The two applications obviously have cross-over, but if you need to see the squall line at 20 NM aft, go for the pulse type. The broadband will, however, allow you to reach your dock during a moonless night and during a power failure ashore.