Pic of my Radar screen. Is this normal?

[Island Dreamer]

Here is a pic of the screen on my older Furuno unit as I went down the channel of a wide harbor and a pic of what was there. I haven't touched any of the buttons like gain etc. I would have though that there would have been better detail that what I was seeing. Not detail in the sense of boat shapes but more of the detail of the channel. Channel was about 125 feet across. I know my equipment is old but about $5k worth of maintenance and other items missed by the surveyor took away my electronics upgrade budget! Are there some adjustments that would make this better?

 

[Mpellet]

RADAR appears to be operating normally but .25 mile scale is too big for that situation. Depending on what model Furuno you have, the RADAR should have at least one if not two range settings smaller then the .25. selected in the picture.

The GAIN, SEA CLUTTER and RAIN CLUTTER settings in an older Furuno like yours are all tuned better manually then AUTO does.

In the picture you posted, first off you should be in a smaller range scale and then manually dial back the GAIN a bit. The false return your getting in the center of the screen will diminish and returns on the rest of the screen will appear less fuzzy.

Those old Furunos are very capable machines for size & price but the auto tuning is a weak point, manual tuning works MUCH better.

Read your manual or do some searching on line to understand the differences, functions and RELATIONSHIPS between GAIN, RAIN CLUTTER and SEA CLUTTER settings. Understanding and knowing how to adjust those features for operating conditions is essential in making an old school RADAR like that Furuno perform correctly.

Based on that picture there is nothing wrong with your RADAR, just needs a little tuning/adjustment.......

 

[Island Dreamer]

Thank you. I couldnt get it below .25. Maybe there is a setting I need to explore the manual to find if it can go lower.
I dont mind that it looks old and is fancy wth colors. I just want to be able to navigate at night or thick fog.
Just downloaded a manual to a similar model.

 

[Island Dreamer]

Confirmed that this unit will not go lower than .25 mile. Can anyone recommend another Furuno that could plug in to the harness I have for this that would be a better upgrade?

 

[GoodChance]

That would be a question best answered by Furuno Technical Services. Call Denton, Maryland or Camas, Washington. Both are excellent.

 

[pelagic2530]

My first thought is that your gain is too high. It appears as though your reflections are "smearing" so that targets on both sides of the channel are blending together, causing a lack of definition and the apparent targets that are across your path ahead of you.

At that range, it's unlikely that you'll be able to see individual boats. But you should be able to see the clear channel ahead of you, with an irregular or "bumpy" edge on each side. Sea/Rain clutter are usually inconsequential at that range, and should be on the low side. My first step would be to try to remain in the same spot, and play with your gain settings until you see something that mirrors what you're seeing visually. Read up on your manual (available online if you don't have a copy) on how to tune the radar. Beware that a lot of the old Furuno manuals tend to be written in "Engrish" and can be a bit tough to follow. Get the model number and check out YouTube, there may be some helpful hints there.

Also, take note of how the radar dome is mounted on your hardtop. Unless it has a downward angle towards the bow, at very low ranges there will be a blind spot around the vessel where the radio waves will shoot over anything in close proximity.

At the end of the day, remember also that that's a pretty tight passage for a small radar unit. The closer targets are together, the greater their tendency to blend or smear together, looking like one target. That's a situation for very minimal power. The old Furuno units are good radars, but you're not going to match the definition of the new high definition/variable pulse/doppler units. But by playing with it a bit, you should be able to get something that is navigationally useful.

 

[Kendall Brown]

I see on your radar display that ES is highlighted. This is a setting called echo stretch and is used at longer ranges to enhance the echo size due to signal loss at long range.
Check to make sure it is OFF at short range use, it may help define your image at shorter ranges.

 

[pelagic2530]

I see on your radar display that ES is highlighted. This is a setting called echo stretch and is used at longer ranges to enhance the echo size due to signal loss at long range.
Check to make sure it is OFF at short range use, it may help define your image at shorter ranges.

KB is exactly right, I missed that entirely (wasn't even sure the smaller recreational ones had that feature!). What you're seeing may very well be just that feature stretching echoes from each side of the channel so that they appear to meet or overlap in the clear channel ahead. Turn that function off and see what your display looks like. After that, play with your gain setting.

 

[Kendall Brown]

Just to give you an idea of what a newer digital radar can do. These images were taken while I was at the dock, one is a top down aerial view of the channel I’m in and the other is from my 4G radar at 1/4 mile range. The white dots are me tracking a paddle boarder riding the outbound tide. You can see his course and range in the MARPA Target box.
The docks are quite clear on the radar image. I can pick off mooring balls 400 ft. away.

As others have stated, tune your unit manually with particular attention to the gain setting and check the ES setting is OFF. Good luck and let us know how you make out.