Radar Not Picking Up All Targets

Jim, I don't see this option in the manual and don't recall seeing it being set when I was reviewing the settings. Can you tell me how to get to it?

Thx,
Alex.

You have 2 clutter settings. STC and RTC.

STC = Sea Clutter. RTC = Rain clutter.

Basically, clutter reduction is a more accurate term. Unfortunately as you increase the clutter reduction you also reduce or eliminate the ability to see targets that are poor reflectors of radar.

This gets back to my suggestion of flipping the auto-settings off except for timing and manually adjusting the gain until you see some speckles or snow on the screen.

Assuming the area is clear in front of your radar array on top of your arch I think you will come back here and tell us you now are able to see all vessels, even very small boats like personal watercraft or flat boats with little freeboard like jon boats. Again, do this with clear, calm, daylight conditions.

I found that once got experience using radar and understood how to interpret what I was seeing on the screen in the best optimal conditions and was able to verify what I was seeing with my eyes I was able to progress to less and less optimal conditions.

This only goes so far. Big whitecaps and small targets like a PWC will eventually become impossible to distinguish at some point. If the PWC is between two waves as the radar sweeps that area the target does not show up. Also the waves themselves become targets. So you turn up the sea clutter settings until you no longer see the waves. At this point small poor reflecting targets disappear.
 
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I have been enjoying the discussion about the angle that the radome should be mounted. .....

I’m going to make a broad statement and it can only be taken so far.

Unless you are “way-off” the dome is not that sensitive to being perfectly level.

Reason, radar is 2 dimensional, not 3 dimensional.

For an experiment try this. Get on plane in an open area with no boats close by for safety. Have a target off in the distance to port or starboard. Now make some zig-zag turns. The target remains even though your boat banks several degrees as you turn back and forth.

Why is this? Let me explain.

Think of the electrons that are being thrown out of the dome as stones. If the angle to the dome to the water is flat the stone will skip away and not bounce back..

Of course this only goes so far, you can only be off by so much.

Please see Page 4 of 13 at this link
http://www8.garmin.com/manuals/1260_GMR21_41InstallationInstructions.pdf

This is from a Garmin installation instruction manual.

"A radar beam can normally be assumed to spread 25 degrees above and below the scanner’s radiating element. For vessels with higher bow angles at cruse speed, it may be helpful to lower the angle so the beam points slightly downwards to the waterline while at rest. "

So you dont want to be way off but you can be off by quite a bit.
 
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I can't tell by the picture of your boat, but is the radome tilted forward while the boat is at rest? The radome needs to be level while the boat is underway for optimum performance, so on most boats, it should have a slight tilt down towards the bow. There are spacers available that will help you to position the radome properly if it is not already set correctly.

This is a good question. It is hard to tell from your pciture how the radar dome is mounted. There are mounting brackets that position the radar dome for maximum efficiency. I have one on my boat that the previous owner had installed. It may be worth consulting with a Raymarine installation professional to evaluate and calibrate your system. The 1/4 nm range is the most critical for collision avoidance.

My radome is simply leveled with on the arch, there's no tilt. It's just bolted to the arch. An interesting point regarding the angle, but the radar gets mostly used (in my case at least) in poor visibility and slow speed (5mph), I love night cruising. So, in this case radome being leveled is a good thing IMO.
 
I think you may have narrowed down your problem. If the radar dome is mounted directly on the arch, your setup may be limiting the abiltiy of the unit to "see" things in close proximity. Changing the angle of the horizontal plane may not be the answer. Getting the radar dome up off the arch and slightly forward, modifying the vertical plane may be the answer. Follow this link to see a picture of a radar mount that does just that. I have a similar mount on my boat and do not experience the symptons that you have. http://www.westmarine.com/webapp/wcs/stores/servlet/producte/10001/-1/10001/70154/377%20710/0/radar%20accessories/Primary%20Search/mode%20matchallpartial/10/0?N=377%20710&Ne=0&Ntt=radar%20accessories&Ntk=Primary%20Search&Ntx=mode%20matchallpartial&Nao=10&Ns=0&keyword=radar%20accessories&isLTokenURL=true&storeNum=5003&subdeptNum=3&classNum=109
 
I think you may have narrowed down your problem. If the radar dome is mounted directly on the arch, your setup may be limiting the abiltiy of the unit to "see" things in close proximity. Changing the angle of the horizontal plane may not be the answer. Getting the radar dome up off the arch and slightly forward, modifying the vertical plane may be the answer. Follow this link to see a picture of a radar mount that does just that. I have a similar mount on my boat and do not experience the symptons that you have. http://www.westmarine.com/webapp/wc...=true&storeNum=5003&subdeptNum=3&classNum=109


In Two Deep, thanks for suggestions. I'll try to go over some setting suggested earlier and will do additional monitoring to determine at what exect situation (on plane or off plane, different ranges, etc.) radar doesn't see the targets.

We might be looking in to KVH M3 sometime in the future, so having this tower for the radar will require M3 to be even higher. I'm trying to be somewhat pro-active to avoid extra hassle in the future.

I'll be doing more testing in the next few days and will keep you guys posted.

Thanks again,
Alex.
 
You have 2 clutter settings. STC and RTC.

STC = Sea Clutter. RTC = Rain clutter.

Basically, clutter reduction is a more accurate term. Unfortunately as you increase the clutter reduction you also reduce or eliminate the ability to see targets that are poor reflectors of radar.

This gets back to my suggestion of flipping the auto-settings off except for timing and manually adjusting the gain until you see some speckles or snow on the screen.

Assuming the area is clear in front of your radar array on top of your arch I think you will come back here and tell us you now are able to see all vessels, even very small boats like personal watercraft or flat boats with little freeboard like jon boats. Again, do this with clear, calm, daylight conditions.

Presentation,
Ones I set the STC from AUTO to manual '0' leaving GAIN and TUNE on AUTO, I was able to pickup those idiots on jetskies flying right next to me (no offense but if one is flying in the anchored area he/she is an idiot IMO).
I'll use it in the manual mode and see how it goes.

BTW Guys, If you're in a relatevely busy area 1/4 is not a small range. I think that on my bay it's a good range. When I'm out in the open ocean it's a different story.

Thx,
Alex.
 
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Hey Alex, that is great news!

A long time ago when I was going thru my frustrations on learning how to use Radar I came across a forum post where a real world user explained in plane English how to manually adjust the STC and RTC. It explained how these two filters are different and gave examples how to demonstrate this.

What you are doing now will work in calm seas with no rain. Eventually you will encounter times where you will want to use radar with poor weather.

When you are ready please let me know and I will past this. Unfortunately I don’t remember where I found it so I don’t know how to give the author proper credit but I did keep the content.
 

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