Radar Help

Cregan13

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Can someone help me out with this? I have limited experience dealing with radar.

The 2006 vintage Furuno radar connected to my 2006 vintage Furuno Navnet has a particular quirk. When I am running down the ICW or any of the side channels it works like a champ. However, when I approach the ocean end of the inlet, the screen looks like a paint splatter. It looks like it is picking up 250 boats all around me. For clarity, there are not 250 boats around me when I leave the inlet. As I proceed offshore, it get's progressively better, but it takes a few miles before I can truly trust what I see on the screen.

What's up with that? Is it some sort of anomaly caused by a radar reflector on the Sea Buoy? Do I have to change settings once I hit open water?
 

SkunkBoat

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If it is on Auto setting (clutter) it may have set to the nice flat calm ICW and It may take a while to reset based on the wave height of the ocean
 

Fishtales

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file:///C:/Users/15088/AppData/Local/Packages/Microsoft.MicrosoftEdge_8wekyb3d8bbwe/TempState/Downloads/sensors-09-01913%20(1).pdf

More that you want, but if you understand it at the 50K foot level, then get the manual (online hopefully) for your unit, you should be able to adjust it. It sounds like it is tailored for the ICW. I would have thought that you would see nothing versus everything in open ocean though. Regardless, likely a setting issue on the plotter.
 

SmokyMtnGrady

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That's clutter. I don't have that brand. Some may have an auto declutter or sea clutter mode . You can manually drop out the clutter by reducing the gain (power) and you can manually adjust it until it goes away, then you can see real boats, the jetties and buoys. My Garmin has a sea clutter mode, rain clutter and auto gain which can all be on or off and tailored to my needs at the time. Good luck.
 

Fishtales

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I agree, but I would have thought he'd see nothing vs clutter as it was set up for the ICW and channels. Am I missing something?
 

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Do you change the range on the radar when you go into the inlet?
 

Fishtales

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I'd get the manual and play with the gain, clutter, rain and other settings that could impact. Looks like a configuration setting issue from here.
 

SkunkBoat

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I agree, but I would have thought he'd see nothing vs clutter as it was set up for the ICW and channels. Am I missing something?
The "clutter" function of a radar decreases gain only at short range. Clutter is caused by returns off the sea.

If the processor sees no clutter(waves), it INCREASES the gain so that it can see even very small targets. If you are navigating a calm channel you want to see bouys, in close. You may even be in a "close range" mode. So if the gain is up and then you get clutter (you exit an inlet and encounter waves) it will decrease the gain so you only see larger targets in close and don't see sea return.

It takes a while for a processor to determine that the clutter is random and not actual targets
 
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SmokyMtnGrady

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I agree, but I would have thought he'd see nothing vs clutter as it was set up for the ICW and channels. Am I missing something?

Well, if for instance the sea clutter mode is off and his range is close in ,then the screen could fill up with the noise from the wave action and the jetties and maybe adjacent condos and such. Where as if the range is 2 mile plus radius the clutter will be near the center and less as you got further out.

Skunk Boat has it right.

When I travel at night for instance , I will increase my gain as much as I can with sea clutter filter on so I can pick up boats, markers , even crab pot buoys if the conditions are right. It's something the OP should adjust in the ICW and get use to seeing with his eyes on the horizon versus what's on the radar while adjusting the noise level.
 
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Cregan13

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I tried changing the range when I first notice the issue, but it did not help and the paint splatters extended through the entire range selected. Next time I am out of the inlet I will float around for a bit and play with those settings. Thanks for all the input.