Odd Radar Reflection?


Furuno Super Fan
Radar Image 1.jpg

Hi: I snapped these odd-looking radar reflections while cruising about 20nm offshore in moderately rough weather yesterday. I thought at first a Racon, but I am pretty sure there are none in this area. There were 2 or 3 large container ships within 10nm or so.

DRS4D and MFD12.

Interference...or something going wrong with my DRS4D that needs attention?

thanks & regards


  • Radar image 2.jpg
    Radar image 2.jpg
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It photo appears to show be what we call "rabbit tracks". These are normally caused by other radars transmitting in your area, being received by your radar. Most likely you or someone has turned Off the interference rejection which filters other radars. You might want to ensure that yours is turned On.
Johnny: you are right, my Interference Rejection was set to Off; my understanding is that I should only turn this on when I see the 'rabbit tracks' and that it should normally be Off, so as not to miss weak targets: have I got that right?

It is user preference. Most run with the rejection turned "On" all the time. When it comes to small targets make sure you are using the radar coastal and advanced setting selection appropriately.