1984 3607 radar mounting location

[JeffandErin]

1984 3607 aft cabin. I purchased the vessel with an open array radar mounted on a platform between the top of the windshield and below the splash screen of the flybridge. Although there is cabling, there was no display unit when I purchased the vessel.
Im now considering adding a functioning radar. So Im debating on where to mount the open array/dome
The boat has a nice radar arch installed that would put the array/dome well above my head on the upper helm and would seem to be the best/most likely installation location.
However, I spend a good portion of my time travelling the Erie Canal that has some low bridges. The arch itself puts my bridge draft at 15 ft. Adding in a radar array on top of the arch could potentially restrict my travel (no the arch cannot be lowered as it is a structural component of the aft deck hard top)
As I said, the previous installation of radar has the array mounted on the a platform forward of the upper helm between the windshields and the flybridge.
I have done a bit of research of the potential harm to persons if the active array were left in that location. It appears that I would not be harming people by doing so.
I also realize that installing a new array in that forward position would create a significant "blind spot" of approx 180 degrees from port and starboard to aft - essentially, I would be blind to what is behind me.

So, I wanted to query this forum. What are your thoughts?
Does anyone have any documented reliable sources of information that stipulate harm to humans?
What are your thought on losing 180 degrees of visibility to your stern?

[Viper]

Up front is not a good location if for no other reason than limiting your coverage, kind of defeats the purpose of having a 360 degree sweep. Put it on the arch and if you must, hinge it back or forward so you can clear low bridges.

[bud37]

I guess if you are mostly in a canal IMO, you really don't need radar at all, least of all an open array.

Now that said, for radar to be the most effective the higher off the water the better, also there will be no immediate interference from the boat itself.

Seeing behind you when in the great lakes shipping lanes is extremely important as those freighters move much faster than most people think and can get up on you without notice in bad weather/night. They can also pick up your signature I believe.

Just a couple points to ponder........

[plittle2005]

On my '92 3307 AC, my bare arch is 15' 6" My arch-mounted Garmin removes or reinstalls in 30 min. 4 bolts and a cable plug.

So I just easily removed it for the Champlain and Western Erie, short term.

Then our guest in the vee-berth "sleeps with the Radar" (he he) for a few days!

[Viper]

Source of the post.....for radar to be the most effective the higher off the water the better,....

It's a little more complicated than that. While height will give you distance due to line of site, there are drawbacks. In rough seas for example, when the vessel is constantly heeling over, the higher the radar is mounted the greater the effect the heeling will have on the radar's ability to produce a clean reflection of your surroundings. That's why you rarely see radars mounted at the very top of sailboat masts, even when they're on gimbaled mounts. A radar's beam is also pretty narrow, on average between 10 to 13 degrees up and down of the radar's centerline. The higher you mount your radar, the less target acquisition you'll have for closer objects around you, they'd be "flying under your radar" Take it from someone who's done a lot of night time running, and been caught in fog, it's a heart stopper when something is suddenly on top of you or vis-versa because you couldn't see your immediate surroundings on the screen. The best location is a compromise with several factors in mind.

While todays designs don't emit the same energy as the older magnetron driven units, they still put out microwaves to do their job. I haven't seen one write up yet saying it's okay to mount a unit below head height and without taking your beam width into account. Simply mounting a unit behind you right above your head as on an arch must also take into account the 12 degrees or so that the beam angle will shoot downward from the unit.

[bud37]

Source of the post Now that said, for radar to be the most effective the higher off the water the better, also there will be no immediate interference from the boat itself.

For the most part IMO everything is more complicated but simply for the ops boat, an approx 40' powerboat, he has an arch and like you said, mount it on the arch. the highest part of the boat, hence the highest off the water for the boat.......

[Viper]

Just putting that out there as general info for all members to consider. I've seen some domes on poles that are way too high for given applications and conditions even though arches are present thinking that the higher the better.

[sbb2112]

This is what I did with ours. The tower is 36" to the radar platform. The base is hinged and is mounted on the top of the radar arch. The sionyx night vision camera is mounted just below and gives a good field of view and the radar gives a decent short range coverage taking in to account the 12 degree up and down beam. I did the dimensional layout and the minimum height I came up with was 18" for just the radar w/no camera platform. The camera is about 8" below the radar platform. The 36" gave a little headroom. I got the tower made at Nautical Creations in louisville,ky. They have examples on their website.