RayMarine RADAR

[TexasEye]

Is anyone having problems with seeing boat targets, I see shorelines and buildings but cannot see boats or buoys. I suspect my bow angle being high is causing the antenna to miss targets???!!!

 

[BB marine]

I don't have a Raymarine radar. I have a Garmin with a GMR 24 xHD dome. I shimmed the dome with jack bolts to get a better running angle. I also adjust sensitivity based on the weather conditions. If I am cruising in poor visibility conditions and know of a none object that is not being picked up and visible on the screen. I will keep bringing sensitivity up until it picks it up. Even running at slower speeds of 7.0 Kts the bow attitude is slightly elevated. Having the dome slightly angled down helps pick-up approaching objects. The dome has has a 25 degree vertical beam width so 12.5 degree above and 12.5 below center line plane of the dome.

This was my easy solution. It doesn't take much shimming to change the angle. I was also able to adjust the horizontal angle with this method also.


Garmin recommends : A radar beam can normally be assumed to spread 25° vertically above and below the radome’s radiating element. For vessels with higher bow angles at cruise speed, it may be helpful to lower the angle so the beam points slightly downward to the waterline while at rest. Shims may be used as necessary.

 

[Connerkip]

Also, perhaps adjusting the gain Would help.

 

[TexasEye]

Hummm...I'm an aviator and used plenty of wx RADAR, all I've used in Aircraft have adjustable antenna's (UP and DOWN) and is a critical component of wx RADAR. I spent hours looking for the tilt control on the boat!. I suspected I was not scanning the water, even dead stop I can't pick up boats and buoys. Looks like I have to pull the shim box outta storage.

Since the RT25 list to PORT noticeably, horizonal shims might be necessary too...

Thanks...

 

[NorthernFocus]

Hummm...I'm an aviator and used plenty of wx RADAR, all I've used in Aircraft have adjustable antenna's (UP and DOWN) and is a critical component of wx RADAR....

Most boats operate at the same altitude all the time. And only care about things at that altitude. Since we aren't fast enough to go around the weather we're more concerned with seeing through it than seeing where it is. So no need to look up. And when angled down it's referred to as SONAR rather than RADAR 😀

 

[TexasEye]

1* change in pitch attitude at 1 nautical mile is 100 feet and 1* of attitude is 10' @ 600 feet, when you consider the bow change is as much as the total scan angle then it is a problem. Adjusting the antenna not only allows the RADAR to scan the Water in the collision radius but it also allows the operator to cut down ground (water) clutter which provides a much cleaner picture. I appreciate your point but the signal has radiate the target and be seen by the antenna when it returns.

 

[NorthernFocus]

1* change in pitch attitude at 1 nautical mile is 100 feet and 1* of attitude is 10' @ 600 feet, when you consider the bow change is as much as the total scan angle then it is a problem. Adjusting the antenna not only allows the RADAR to scan the Water in the collision radius but it also allows the operator to cut down ground (water) clutter which provides a much cleaner picture. I appreciate your point but the signal has radiate the target and be seen by the antenna when it returns.

If one is really concerned with optimum performance in all operating regimes then perhaps a gimbal mount such as those used for mounting radomes on sailboat masts is the solution. Of course on a Ranger it would need to be installed sideways to accommodate fore/aft attitude change rather than heel angle.

 

[BB marine]

You can use the same mount and use threaded rod with jam nuts and finish nuts (acorn) to make all adjustments. The Garmin mounting hardware is metric. 8MM stainless steel threaded rod. You would have to see what Raymarine mounting hardware is. When all rods are installed in the dome adjustments are very easy to make. After final adjustment, jam nuts are tightened. This is not a something that you change based on conditions. It is an adjustment that is made based on normal running attitude of the boat. I have had no issues with this. Two boating seasons 250 running hours and 2000 miles over the road.




When we took delivery of our boat the mast radar mounting base was bent. With no success in getting it repaired by the factory or dealer. I purchased the hardware to adjust the dome. This method gave me the ability to adjust vertical ( recommended by Garmin) and horizontal ( level port to starboard because of factory defect )

This is how it looked when we purchased the boat.


This is a photo showing the dimensions of the offset of the dome mount


This is photo of dome level and angled down approx. 5 degrees. Don't pay attention to the idiot holding the loop flag!

 

[TexasEye]

You can use the same mount and use threaded rod with jam nuts and finish nuts (acorn) to make all adjustments. The Garmin mounting hardware is metric. 8MM stainless steel threaded rod. You would have to see what Raymarine mounting hardware is. When all rods are installed in the dome adjustments are very easy to make. After final adjustment, jam nuts are tightened. This is not a something that you change based on conditions. It is an adjustment that is made based on normal running attitude of the boat. I have had no issues with this. Two boating seasons 250 running hours and 2000 miles over the road.




When we took delivery of our boat the mast radar mounting base was bent. With no success in getting it repaired by the factory or dealer. I purchased the hardware to adjust the dome. This method gave me the ability to adjust vertical ( recommended by Garmin) and horizontal ( level port to starboard because of factory defect )

This is how it looked when we purchased the boat.


This is a photo showing the dimensions of the offset of the dome mount


This is photo of dome level and angled down approx. 5 degrees. Don't pay attention to the idiot holding the loop flag!

Great info BB, Thanks, I have already started my mod. I'm working on using a laser level adjustment mechanism I have as scrap (can't thow nothin' away), if I can post pictures I will. I also have a nice selection of aircraft landing geat shims used to alleign the wheels, I know that will work.


Tex