False circular target

[Anonymous]

My 1833c is showing a false target of a symmetrical circular shape near to the boat (50 meters away, maybe). It's all the way round the boat on the display in a thick, red ring on the display. Targets dhow outdide it. Any suggestions?

Thanks.

 

[Johnny Electron]

It sounds like you have water/moisture inside your radome. I would recommend removing the dome cover and inspecting.

 

[Anonymous]

Ok, thanks for that. I have opened it up and it's dry and clean inside as far as I can be sure. The problem remains though. Ideas...?

 

[Johnny Electron]

If the timing adjustment is off extremely, or someone has made the scanner cable longer or shorter than allowed; can cause a ring. Objects/items mounted close around the radar or painting the antenna with the wrong paint can reflect radar energy and cause rings. If none of that applies it might be a bad circulator or other internal issue inside the scanner; or video processing inside the display unit. It would have to be evaluated by a qualified tech.

 

[Anonymous]

I have a similar problem.
I installed a Furuno display radar FR8122, RSB0073-086 gear box and irradiator XN13A on a cargo vessel.
When I turn on the radar all was OK, except that in the image appeared a ring around the origin how you can view in the photo.
I try to adjust the configuration but the ring in the image did not disappear.
I have sought information about the problem but I could not solve it.
Before installing the unit, I had an accident where the radiator fell into the water. I dried the radiator to be sure to removed all the humidity. The worst scenario for me is that the problem is caused by this inconvenient and that the irradiator is damaged.
Please support me to solve this problem.
Best regards.

 

[Johnny Electron]

Before installing the unit, I had an accident where the radiator fell into the water.

As I stated with the first customer, water is a typical cause.
If the radiator fell in the water, you would have needed to dry it out on the inside and maybe even leave in some rice or other method to ensure all moisture is removed. Even if you dry something by hand, air can hold moisture. When it gets hot and cold it will condensate. Radar will bounce back from the water droplets and cause the ring. If you allow water to get from the radiator to get into the radar waveguide, then you really have even more problems. I would recommend you contact you local dealer/distributor.

 

[Anonymous]

As Johnny said, it could be moisture inside of the array. The problem that happens around here is the boats have 2 generators on them and they only use one a time. Sometimes when they switch without powering down the unit it knocks down the sweep timing adjustment. Best thing to do is contact your local Furuno dealer and have them take a look at it and see if there is anything out of the ordinary.

Keith

 

[Anonymous]

Thanks for the support. To rule out the possibility that the humidity is causing the problem, I removed the radiator to completely eliminate it. However ring persisted around the origin. The cause was the timing adjustment. Although the settings made I could not get the image on the screen is clear. For example, I can only display the contours of the sand banks, and I have some false measurements on the surface of the river. The image is observed as if the gain of the radar was low, I think it must be related to the transmit power but do not know how to set this parameter. I am from Paraguay and the nearest dealer for FURUNO is in Argentina, but is always difficult to contact them.