Upgrading radar questions.

[Bi111ion]

I have an old Furuno radar on my 39 foot ketch. It works fine but it is mounted above the chart table and sailing short handed I need to see it in the cockpit. I have tried improvising with an IP camera and then view on phone or tablet but of course cant play with settings so I am hankering after a newer radar. I know Garmin and Navico (ie SImrad B&G etc) output data over an ethernet that can be displayed in OpenCPN and that is nice as I have a computer at the chart table running OpenCPN. I understand I need a "multi function display" MFD, ie a chart plotter+ to control the radar and I was thinking of fitting that in the cockpit. Does the MFD have to be the same brand as the radome? Is there some standard protocol for controlling the radar over the ethernet? How do I choose between the fancy new types of radar anyway. It is mainly for collision avoidance and back up navigation, so has to work well enough when healed and have minimum current consumption I suppose.

 

[pvb]

Does the MFD have to be the same brand as the radome?

Effectively, yes it does.

Edit: just to expand and clarify, B&G, Simrad and Lowrance radomes are identical and will work with displays from any of those 3 brands.

 

[laika]

Is there some standard protocol for controlling the radar over the ethernet?

As with pvb's reply to the compatibility question, this stuff is currently proprietary. My understanding however was that there was a radar working group involved in the NMEA OneNet standard which offers the promise of a radar standard in future, not that I've even heard of any OneNet products yet.

I have no personal experience of it but the Furuno DRS4W is designed to work with ipad/iphone if you want to avoid buying an MFD. Doesn't work with OpenCPN as far as I know.
FURUNO 1st Watch Wireless Radar

 

[RobbieW]

Adding a little to the previous answers; that OpenCPN supports some Garmin and Navico scanners is because a few capable people reverse engineered the data streams and protocols and built support for those into a plugin - FAQ Radar [OpenCPN Manuals]

 

[Bi111ion]

So suppose I just take the analogue signal from my old Furuno (it is a 1621), the coax cable, and put it through a video rate analalogue to digital converter, it I had a synch signal from the rotation I could just write a few lines of code to display it in polar coordinates... maybe a little signal processing. DYI radar display on an RPi? Now I say it surely someone has already done that! Am I missing something here? In the old days (like 1970s radar on a CRT) they just displayed the raw data on a CRT.

 

[prv]

I have no personal experience of it but the Furuno DRS4W is designed to work with ipad/iphone if you want to avoid buying an MFD.

I don't have any personal experience either, but from what I've read this seems to have been a bit of a product-line dead end. A WiFi and app front-end stuck onto one of their older radar models, almost as an experiment to gauge the market. Sadly (because I like the idea of not tying radars to specific plotters) it doesn't seem to have gained much traction and they don't seem to be continuing with the concept.

Pete

 

[Jamie Dundee]

If you get Simrad/B&G mfd with wifi output you can both echo and control radar/chart etc from a phone/tablet. I’ve set up an outside station for a tablet so I can check chart/sonar when fishing without peering into the wheelhouse. The tablet controls the NSS evo3 via wifi

 

[prv]

So suppose I just take the analogue signal from my old Furuno (it is a 1621), the coax cable, and put it through a video rate analalogue to digital converter, it I had a synch signal from the rotation I could just write a few lines of code to display it in polar coordinates

If you have the skills to do it, it seems a plausible project. Is the Furuno cable just coax? The analogue Raymarine radars had a coax for the video, plus about half a dozen plain cores one of which was the sync signal for rotation. There was also a comms channel (presumably some kind of serial) for miscellaneous data about the scanner, and commands like range control. I suppose if you kept the below-decks unit and just picked off the picture signals for an auxiliary display, you might not need to reverse-engineer the control side, but you'd definitely want the service manual before making a start.

I don't think this is the most sensible way to just get a radar picture in the cockpit, but it sounds like a fun project if you like that kind of thing.

Pete

 

[Bi111ion]

I don't think this is the most sensible way to just get a radar picture in the cockpit, but it sounds like a fun project if you like that kind of thing.

By far the simplest thing to do is use a camera, which is a bit ironic as all the huge amount of work has gone in to making small cheap cameras and IP camera aps for phone and its vastly more complicated but now very easy to get to work. Especially given the signal from a radar is basically just a video signal in polar coordinates.

But that said my first stab at a remote control I could use for the helm to activate the autopilot was a long stuck. What we (me and my friend who knew more about microcontrollers as his son did a school project) did in the end was use a very cheap 8 bit microcontroler to inject an "auto pilot on" signal to the Raymarine Seatalk buss connected to a waterproof push button at the help. It involves about a page of C-code. ... but I wasnt going to pay what Raymarine wanted for a remote control! And it was fun.