Chartplotter with 4G Radar - B&G or Simrad

[Dockhead]

[QUOTE=sailjumanji;1767438]

Originally Posted by CAELESTIS

I think you are good. Here is what the commissioning guide says about the smart pilots. "S2 & S3 have 10 Hz, 0.1 deg resolution, suitable for use with MARPA function or radar equipment." If you have the G (gyro) in addition, I would suspect you are golden.

Dockhead, why the Simrad GS25 instead of the B&G ZG100? Not sure about the Simrad, but it sure looks similar to the B&G. And the B&G specs say "integrated electronic compass for accurate boat direction and radar/chart overlay. NOT SUITABLE FOR USE WITH MARPA." So is this just a disclaimer for legal purpose or can it really be that far off for tracking other boats?

Maybe I still don't understand MARPA. Or ARPA. Is that tracking by radar combined with AIS?

Yes, the gyro version of the Raymarine compasses is pretty good -- no need to change if that's what you've got.

The GS25 and ZG100 are exactly the same units for the same price. Only difference is the name on the box.


"ARPA" stands for "Automatic Radar Plotting Aid". It has existed for decades and has nothing to do with AIS. It just does by computer what radar operators are trained to do on a plotting sheet -- tracks a contact through a number of sweeps and analyzes the motion of the contact. It works pretty well on ships with their big, powerful radar sets, but in my experience doesn't work as well on recreational radar - probably because the limitation on accuracy of bearings (our radars are very accurate for range, but not very accurate for bearing). See: Automatic radar plotting aid - Wikipedia, the free encyclopedia

"MARPA" is "Mini Automatic Radar Plotting Aid" -- ARPA with some reduction of features for recreational use.

Neither of them can do anything particularly different from what you can do with a plotting sheet. The value of radar to you will be enormously enhanced with study or a class. Radar is not the kind of thing which you can really use effectively just by switching it on and using it. See for example: Tim Bartlett, journalist and author, background information on sailing and motorboating topics

The RYA give great radar classes.

[tanglewood]

Originally Posted by goboatingnow

do not change merely to get 4G broadband, in reality, there are just different tradeoffs, pick a chart plotter and get the accompanying radar.

I did this, and it was a big mistake. I assumed all radars were more or less equivalent. After all, the technology has been around for a really long time. Should be like buying a TV, right? Not so.

If you use and care about ARPA, the Navico products' is pretty seriously broken. Here are details with videos showing the problem. I ended up removing all my Simrad gear because of this and a slew of other bugs.

If you don't know what ARPA is, or don't care, then never mind.

[tanglewood]

Originally Posted by Dockhead

"ARPA" ..... works pretty well on ships with their big, powerful radar sets, but in my experience doesn't work as well on recreational radar - probably because the limitation on accuracy of bearings (our radars are very accurate for range, but not very accurate for bearing).

I had great success with ARPA on a Furuno NN3D with 24" dome radar. Definitely a recreational system, but the ARPA worked very well. Going from that to Simrad is what alerted me to how f&*ked up Simrad's ARPA is.

[Dockhead]

Originally Posted by tanglewood

I had great success with ARPA on a Furuno NN3D with 24" dome radar. Definitely a recreational system, but the ARPA worked very well. Going from that to Simrad is what alerted me to how f&*ked up Simrad's ARPA is.

I've never tried a Furuno set, and would like to.

I've used various Raymarine sets, on which MARPA works about the same or even worse than my B&G.

But I'm not sure that ARPA is really very important, if you have a good AIS set, and you know how to interpret a radar screen. How often do you need to know CPA, course, speed, etc., of a small vessel? This kind of information concerning a small vessel is generally useless. I put the EBL on radar targets and you see at a glance as much as you typically need to know about the kinds of vessels which don't carry AIS.

[44'cruisingcat]

Originally Posted by Dockhead

Not really a bummer. It's a nice MFD. I have the Zeus T -- also obsolete. It's the nature of marine electronics that you almost never have the latest and best of everything

Yeah, but I really like the look of the B&G's sailing software.

[sea-bee]

I believe that one difference between Simrad and B&G is that the Simrad MFD has a sonar input and can run a forward scan sonar. The port is apparently missing on the B&G hardware. If you want the sonar on a Zeus2, you have to pay for a Sonarhub blackbox that costs almost as much as a 7" display.

Originally Posted by Dockhead

I think it's a fantastic idea. The 7" Zeus is so cheap --- like an ordinary instrument was a few years ago -- why not have several of them, if you have space? If I had space, I'd have one 9" one and two 7" ones -- keep one on SailSteer, one on radar, one on chart all the time. Shut one or two down offshore.

So if you want two MFDs, would it work to buy one Zeus2 for the Sailsteer screen and buy one Simrad for the chart which would also allow for a sonar?

And if you have 2 MFDs, then you could run 2 wifi outputs and choose which screen to throw onto a tablet.

[poiu]

Originally Posted by Dockhead

I've never tried a Furuno set, and would like to.

I've used various Raymarine sets, on which MARPA works about the same or even worse than my B&G.

But I'm not sure that ARPA is really very important, if you have a good AIS set, and you know how to interpret a radar screen. How often do you need to know CPA, course, speed, etc., of a small vessel? This kind of information concerning a small vessel is generally useless. I put the EBL on radar targets and you see at a glance as much as you typically need to know about the kinds of vessels which don't carry AIS.

I put this issue on a new thread. I hope some users can shed more light on it:

Furuno ARPA - Cruisers & Sailing Forums

[Safari38LH]

I switched from a Garmin chartplotter and Furino radar to Simrad three years ago and am very happy. On our 38 ft sailboat I have two NNS, one below at Nav and one at the wheel, AIS, G4, and weather. The radar is incredible and draws nothing compared to our old one. I prefer the Navionics charts. We spent two months in Nova Scotia using Simrad and am very glad we had it. This year we are removing our Raymarine autopilot and putting in a Simrad autopilot computer and servo.


Sent from my iPad using Cruisers Sailing Forum

[cwetto]

Originally Posted by sailjumanji

Really hate it when working for a living gets in the way of planning modifications on the boat. Am back now. REALLY appreciate all of the input. Have been reading up on some reference material as well, and am leaning toward a B&G system with 4G radar. Some questions though:

[*]Looks like a heading sensor is required. Can that come from the S1 wheel pilot? Anybody done this? I cannot see changing out a wheel pilot I like and works well. [*]I have read some nightmare posts from people who bought this Zeus and 3G or 4G system and has real problems getting things to work, plus really felt the technical support was horrible. One said he was happy he got it at West Marine with their satisfaction guarantee, because he eventually just returned it all. That was almost two years ago. Any better now? I have had decent experience with Raymarine support, and I read some pretty bad complaints about them too. [*]Internal GPS. Is this really going to work if the unit is under a fiberglass hard top? Right at the edge, and near windows, but still?

Re: internal GPS and gyro: Z12 touch (1.ver) installed in inox console in cockpit of sailing boat with internal GPS almost unusable!
Thanks god, zg100 is cheap and excellent device. For 4G marpa I went for rc42, maybe airmar is better choice, but I am satisfied so far.

[tanglewood]

Originally Posted by Dockhead

I
But I'm not sure that ARPA is really very important, if you have a good AIS set, and you know how to interpret a radar screen. How often do you need to know CPA, course, speed, etc., of a small vessel? This kind of information concerning a small vessel is generally useless. I put the EBL on radar targets and you see at a glance as much as you typically need to know about the kinds of vessels which don't carry AIS.

It sounds like AIS has been more broadly adopted by recreational boaters in the UK. I wish it were so around here.

There are many ways to skin a cat, and what you do obviously works. Personally I find ARPA incredibly useful. The heading vectors give a quick visual of what other boats are doing, just like if they all had AIS. And for those boats that are of concern, you can then look at CPA and/or relative motion vectors to sort out what to do. EBLs work great, but most radars only have two of them, so if you have a half dozen boats coming at you they can be problematic.

[Pyxis156]

Originally Posted by sailjumanji

Ok, so for some costs. The Simrad NSS Evo2 with 4G, 9 inch screen, can be had for $4200-$300 rebate = $3900. Yeah, I probably will have to buy the RC42N rate compass, and the external GPS antenna (hardtop overhead). But that is the same for any unit. Guess I would give up Sailsteer. Another thing I have to look into is whether my ST60 wind can get whatever Sailsteer needs to it. It is not in the NMEA output from the autopilot, although all of these are linked together via Seatalk.

The Zeus2 is not available in a package. It's roughly $2500 for the 9 inch display, plus another $2000 for the radar. So $4500.

If I want to go with Zeus Touch and 4G, then $2700 for 8 inch and $3100 for 12 inch. So what do I give up going Touch system. Besides a bunch of cash outlay.

Thoughts? And another thanks for all of the input/feedback/advice. I have not had luck with West Marine understanding the products, as the guys really don't know them. No where else to see them. And last time I was in there, the B&G wasn't even powered up.

Just a head's up, B&G has some pretty decent rebates on their equipment through March:
http://www.bandg.com/en-GB/Offers/Up...?newlang=en-GB

Also a thought on heading sensors. I had the Airmar on our last boat and was very pleased with it. The only negative was that to update the firmware, you needed an Airmar N2K/USB gateway. I already had a Maretron gateway as well as one from Rose Point for my Coastal Explorer chart plotting software and couldn't bring myself to get a third just for updating Airmar products. I am now preparing to refit our new (to us) boat's existing Furuno setup with an all B&G setup, with the exception of the heading sensor which I think I am going to try the Maretron SSC200. The specs seem very close to the Airmar and importantly to me, I can use my existing Maretron USB100 gateway to update firmware as necessary.

Hope this helps...

[Dockhead]

Originally Posted by tanglewood

It sounds like AIS has been more broadly adopted by recreational boaters in the UK. I wish it were so around here.

There are many ways to skin a cat, and what you do obviously works. Personally I find ARPA incredibly useful. The heading vectors give a quick visual of what other boats are doing, just like if they all had AIS. And for those boats that are of concern, you can then look at CPA and/or relative motion vectors to sort out what to do. EBLs work great, but most radars only have two of them, so if you have a half dozen boats coming at you they can be problematic.

It sounds like you use it the same way I do. I also find by far the most useful thing about ARPA/MARPA to be the heading (actually, COG) vector extension line. I do not find the calculated CPA/TCPA to be very useful because small vessels don't usually hold very steady courses.

Naturally, you are right, that the EBL is no good if you're dealing with a multitude of targets. But if you're in a swarm of small vessels going in all different direction, I submit you've got bigger problems, and that these electronic means are of limited value. Here is one case where I can imagine that a very accurate ARPA set with automatic target acquisition might really be uniquely useful. You'll have to report back when you've tried this feature.

[sailjumanji]

Originally Posted by Pyxis156

Just a head's up, B&G has some pretty decent rebates on their equipment through March:
Upgrade to B&G

Hope this helps...

Unbelievable. Thanks for that. I spent two hours in West Marine store on Saturday, playing with the Zeus2 unit with one of the guys there that had some knowledge, and he never mentioned it! I actually found another link that showed the Zeus2 9 rebate at $300, and the 4G radar at another $100.

Ok, back to the questions. I am going to buy the Zeus2 9 and the 4G radar. Currently have an ST60 speed/depth, an ST60 wind, and a Raymarine series 6000 controller and an S1 autopilot. The AP does not have a gyro. All of these are linked together with Seatalk 1 cables. The WM rep says the easiest way to get data from them is a Seatalk 1 to Seatalk ng converter kit. As the three units are daisy-chained together, one cable link at the end should make all of the system data available. And then the converter kit just links to an NMEA2000 backbone via another cable. Does that sound viable? If so, that would get wind data, rudder angle, paddle wheel speed (is this really needed, because most times we have that pulled so as not to deal with marine growth), heading, apparent wind, etc - all into a NMEA 2000 system.

As I said before, the Zeus display unit is going to have to be mounted with the standard bracket, and not flush mounted. My Garmin is the same way. After use, we disconnect the cables and put the unit below, to keep it from walking off! The WM rep was really concerned about the frequent unhooking and reconnecting of the cables, and whether the connections might eventually break because of it. Truth told the Garmin GPS I have now is probably suffering from that, as the power cable is difficult to get on/off. Am thinking that the only connections to the Zeus are probably going to be Ethernet (radar) and NMEA2000 cable. Given that, it might be best to have short pigtails that stay on the Zeus, and connect to Ethernet and NMEA ends of the system. If the pigtails or connectors wear out, they can be replaced cheap. Wont be messing up the Zeus connectors. Does that make sense? Anything better? I wish I Ga place to flush mount it securely, but no chance.

Am thinking I might go with the ZG100 external GPS antenna with compass, and see how well that might work for heading info instead of the S1 compass. The S1 is 5Hz and MARPA and radar overlay wants 10 Hz - from what I have read. Apparently the ZG100 has a 10 Hz compass with gyro, although they warn against using it for MARPA. Something about no yaw. Am I misguided in thinking that yaw is probably not a big issue on my 20 ft wide cat? Anyway, I thought I might give it a try as Dockhead said the integral GPS was not so good, and it will be under a fiberglass hardtop. Or would you recommend just trying it with integral GPS and the S1 compass first, and then switch if problematic? From a radar overlay and MARPA situation, how would you know it is not good enough- re the compass?

A few really stupid questions (sorry).

1. Any reason not to use the Simrad NMEA2000 MicroC connectors and cables to build the network. Anything just as good for cheaper?
2. The NMEA 2000 network requires power cable. It appears that once that is powered up, then Zeus is powered as well?
3. Re power, what about Seatalk ng converter kit, that is connected to the backbone. So it would be powered. But all of the ST displays and the S1AP have their own separate power connection. I guess that is ok, since the Seatalk 1 connected to the converter is just data wires?

Ok, what about AIS. The WM rep - who had done a few trips - felt strongly about transceiver and not just receiver. I didn't realize until then that the AIS needs its own GPS. If the NMEA2000 network has GPS, then does the AIS need dedicated GPS/separate antenna? Not a huge deal to put another one on the arch, but not if it is just redundant. He recommended a Em-Trak B100 AIS Class B transceiver ($580) and a Em-Trak S100 AIS antenna splitter ($260). Cheaper than others, and he had good experience with customers. Reviews are so-so. Looks like it would hook up to the NMEA2000.

Ok, that said, my VHF is so old that is doesn't even have DSC. So probably time to replace it. Ideally what I would like is to see the AIS on the Zeus, and have an easy way to call ship on the VHF. thought I read something that basically dials them up after making a selection? Is that doable? AIS is something that I would probably use more than radar, as we do some motoring in ICW and shipping lanes, and would be nice to call ships by name instead of "eastbound tow at mile x this is westbound catamaran..." Got any recommendations? I like Icom, but the networking with Zeus and AIS is probably most important.


THANKS AGAIN FOR THE HELP AND ADVICE. Looks like I am going to be spending about twice as much as I thought I had conservatively budgeted for. I keep telling my wife - who is a Safety professional - that it is all for safe voyage!

[sailjumanji]

Oh, it looks like the radar RI10 box wants its own power supply, although it is connected to NMEA 2000 backbone for data?

[CAELESTIS]

Sailjumanji, you are doing almost the exact same electronics change as myself. You do need the Seatalk to Seatalk NG to get the data to/from the ST60's.

On the rebates, the B&G wifi is free with certain items purchased. Rather than go with two chartplotters as I have now, it will be a Z2 12in at the helm and iPad at the nav station.

Not sure about the power.

My local WM also suggested the Em-trak, but I am going to connect my Vespermarine 850 to the Z2.

I would wait on the GPS antenna until you have it running. It is very easy to add later.