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Old 06-08-2008, 08:46   #31
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The danger from a boat radar mounted on the mast is minimal. The danger from the same rader mounted on a pole depends on the site of the pole and its angle to the cockpit occupents. The radar has a vertical beam width (each are different) provided you are out of that vertical beam width and/or at least a metre away from the scanner, there is no problem.

Military radars are a very different problem due to the power that they transmit. The concentrated beams used in missile control are so powerful that they have a minimum safety range for aircraft etc.
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Old 06-08-2008, 09:12   #32
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When you move it to the mast, do a little math. Most radars have a 25 degree vertical beam width, and can be counted upon to depict minimal targets at about half their advertised range. Going higher gives you a more distant horizon, but its a waste of time to mount at any higher than enough to see a six foot tall object at that effective range. Go too high, and you will lose things under your radar, as in bouys will disappear when you get close. You will still see big ships and tall buildings out near its advertised range. For my 4kw radar I mounted it 28 feet above the water. I lose small bouys about 100 feet ahead of the boat. I think 22 feet above the water would have been better for my purposes.
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Old 06-08-2008, 09:56   #33
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Quote:
Originally Posted by surfingminniwinni View Post
Does anyone want to buy a used radar????
Maybe... I'm hunting for one. What kind and how much? (you can PM me if you want)
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Old 07-08-2008, 05:38   #34
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Originally Posted by anotherT34C View Post
Maybe... I'm hunting for one. What kind and how much? (you can PM me if you want)
Sorry that was just aussie humour, not really selling.

Boat has mast out for re rigging & spray job, radar going up the mast.
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Old 07-08-2008, 08:31   #35
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Radar ain't so tough.

Well, let me put it this way,

On a submarine bridge, there aren't very many good places to stand or to mount a radar. We typically have two: one mounted on a removable stanchion, and one on a hydraulically operated mast that is housed in the sail. When we have the full maneuvering watch set, the officer of the deck (yeah that's me) and the captain end up standing atop the sail, and the (fairly powerful) hydraulically operated radar rotates and radiates just below waist level. The removable radar radiates right about at head level. When the full maneuvering watch isn't set, there is room for the OOD and lookout in the bridge cockpit, and the radars are above both our heads (but not by all that much). I've spent many an hour in these positions, and we all made many jokes about it onboard.

That said, my wife recently found out she's pregnant with our second child , and she became pregnant with our first while she was still on the pill. So it looks like the little swimmers are doing just fine, thanks.



Radar's not so tough. Don't sweat it.

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Old 10-08-2008, 19:27   #36
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First of all karletto, newbie moderator here. I hit the wrong button...my apologies. I put your post back as it was.

Karletto, radars do indeed have a very narrow horizontal beam width. Some ship radars can be around a one degree. The vertical beam width on radars can be significant. How much? I have passed under bridges and on the radar scope, seen the bridge until I was almost completely under the bridge. The reason for the significant vertical beam width is so that as the ship rolls and pitches, the radar does not lose "sight" of the water.
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