OpenCPN and Navico 3G radar - output not making sense

[jonathanv]

I've recently installed a (second hand) Lowrance 3G radar where my old Raytheon Pathfinder 2kw radome sat. I am using OpenCPN with the latest radar plugin to view the radar output.

I am able to connect to the radar, activate it and control all the aspects of it but the output signal just isn't making much sense to me. Bare with me though, it might be user error as this is the first time I am working with a radar and might just as well not know how to configure, operate and interpret the output.

Some of the perceived issues:
- Whether I am on open water with a coastline nearby or moored up in a big marina, the output looks the same.
- When set to close range, I only see this big red donut-shaped ring.
- When set to long range, I get some thin strips of returns but none of them seem to correspond with the physical world.
- Each scan, the output seems to change even though I am stationary.

The images attached were taken on open water, with land probably 5nm away and some small sailing vessels close by. I cannot see any signs of either the land or the boats on the returns. I have attached three different ranges, 24nm, 12nm, and 1.5nm.

Have I bought a dud? Or could it be some issue in my wiring or the configuration of the radar? I didn't have a chance to connect my laptop directly through ethernet to the access point but could try that next.

My setup is as follows:
- Lowrance 3g radome sits about 9 meters high on the front of the mast, about 1 meter below an Echomax radar reflector
- Radome is connected to the RI-10
- RI-10 is connected to a wireless access point
- Wireless access point has its multicast base rate modified so that it will support the radome data rate over wireless.
- The laptop I am using is connected over WIFI to the access point
- I don't have a heading sensor attached to the RI-10 (just yet)
- I don't have a Navico radar plotter interfaced with it
- Software running is Open CPN 5.2.0 and radar_pi 5.1.4-ov51

[Hakan]

jonathanv..
1. Get you a standard Internet patch cable from the radar antenna direct to the PC. Or from the RI10 to the PC to skip the wifi. Very few wifi routers can handle the massive data flow from the scanner and the result may be as of your pictures.
Read more hear and not less the wifi info: https://opencpn.org/wiki/dokuwiki/do...e_installation

2. For radar overlay on the chart you need a compass and a heading (HDM/HDT) into OCPN, NMEA0183, or to the RI10, NMEA2000.


I've a 3G direct connected to OCPN and cheep compass into OCPN. Works fine.

[Reefmagnet]

Definitely try it on a hardwired Ethernet connection. The multicast radar output causes more problems then it solves on wifi.

It does look like the gain and clutter settings are not set correctly, though. Have you tried tweaking these?

[jonathanv]

Thanks Hakan & Reefmagnet, I'll hardwire it directly into my laptop this weekend to see if the output changes and circle back.

[Douwe Fokkema]

Wifi is indeed unreliable. It may skip packages, causing incomplete images. But I have never seen the donut shaped ring that you have. I am afraid that something could be wrong with your radar.

The opencpn.log file might tell something more about the functioning of the radar software, I could take a look at that. But it won't tell if your scanner is out of order. However, if the software is running fine, the connections are OK and the image makes no sense, the scanner will be wrong.

And by the way, don't pay too much for second hand Navico radars. It seems that the 4G is being dumped now, on offer (new) for 1200 euros at least in the Netherlands.

Douwe Fokkema

[jonathanv]

Originally Posted by Douwe Fokkema

Wifi is indeed unreliable. It may skip packages, causing incomplete images. But I have never seen the donut shaped ring that you have. I am afraid that something could be wrong with your radar.

The opencpn.log file might tell something more about the functioning of the radar software, I could take a look at that. But it won't tell if your scanner is out of order. However, if the software is running fine, the connections are OK and the image makes no sense, the scanner will be wrong.

And by the way, don't pay too much for second hand Navico radars. It seems that the 4G is being dumped now, on offer (new) for 1200 euros at least in the Netherlands.

Douwe Fokkema

Thanks Douwe. Yes, I've seen the offer you mention (I live in NL as well) so I was a bit bummed as I'd only bought it this winter. But, that's how it goes with electronics...

I'll have a chance to test it this weekend so I'll pull the logs and share it.

[Recy]

Maybe there is a 5G in the pipe.

[Andreas29]

Hi,

do you have set a dead zone in the settings (main bang size or so under Installation)?
I know this Donat when using incorrect settings for this.

Regards

Andreas

[Mattzilla]

Originally Posted by jonathanv

Thanks Douwe. Yes, I've seen the offer you mention (I live in NL as well) so I was a bit bummed as I'd only bought it this winter. But, that's how it goes with electronics...

I'll have a chance to test it this weekend so I'll pull the logs and share it.

I have a similar issue - how did you go with your testing?

[jonathanv]

Originally Posted by Mattzilla

I have a similar issue - how did you go with your testing?

Sorry for the late reply but hopefully better late than never. It took me a while to find a second hand plotter so that I could test it.

In the end I got a HDS9 Gen2, hooked it up, reset the scanner to factory defaults but sadly the results where the same. I got in touch with Navico support and shared all the details plus videos and they declared the scanner to be dead or at least beyond repair.

As the unit was probably about 10 years old, they offered me a new 3G radome or a 4G radome for a somewhat discounted price (EUR 1050 for a 4G).

I know there are newer models like the Halo but that would mean upgrading the chart plotter as well as its not compatible with the HDS9 Gen2. This seems a good compromise.

[Mattzilla]

Thanks for the update.
In the end I had same issue as you - unit failure. Have now added a Halo20+ and works like a charm.
Thanks for getting back to me.