Mounting Angle for DRS12A

[remotecaptures]

I installed a radar arch on the trailer and when I put the boat in I used a level app the measure the angle of the mounting plate on the arch where my DRS12a sits. The mounting plate for the radar has angle of -4° (the bow is higher than the the stern). I haven't used the radar other than at the dock but assume I should shim the back of the radar with washers or a plate to around +4° so that it still can see the water while underway, even if the radar has a vertical beam angle of 22°. Planning on getting out this weekend in fog and want to make sure I'm setup correctly.

 

[Sparky Wire]

Even when level, it isn't uncommon for people to place a wedge to allow compensation for when the bow pulls up during cruising/operations.

 

[Johnny Electron]

I agree. I think many marine stores sell various types of wedge mounts for radars.

 

[Quitsa]

It would be a good idea to try and measure the running angle of the boat at cruise speed and at displacement speed. With a bit of simple geometry, you can calculate the distance forward where the center, top, and bottom of the beam will hit the water. Generally since the most critical use of radar will be in limited visibility in fog or at night, you will not be running at a fast cruise speed. If you have an iPhone, the measurement app that comes with it has an angle display that is pretty accurate. Even better is to use the pitch reading from an SCX-20 or other satellite compass. A lot of boats tend to run bow high at slower speeds, which is why shims are popular.

The wide radar beam angle is pretty forgiving but the radar will definitely work better if it is mounted so the beam is aimed properly.