Click for Lurssen Click for Cheoy Lee Click for Abeking Click for Llebroc Click for Westport

Radar mount?

Discussion in 'Silverton Yacht' started by DaddysGirls, Oct 15, 2010.

You need to be registered and signed in to view this content.
  1. DaddysGirls

    DaddysGirls New Member

    Joined:
    Sep 25, 2010
    Messages:
    16
    Location:
    Longport NJ
    I have a soft top & prefer not to get a radar arch. Anyone know what mount I need so I can mount the dome on the front of the bridge below the windshield? What pitch & angle is that or do I just build it up with a shim?
  2. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,379
    Location:
    My Office
    Hi,

    I would imagine that the equipment manufacturers will have some numbers re where it needs to face in relation to the horizon.

    The lower you get it onboard the less of a useful range you will achieve ( Height of eye above horizon).

    Also remember that if your boat is dragging it's stern and the bow is aimed at the sky the radar picture won't be of much value except for the odd bird watching or ATC Practice.
  3. NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,214
    Location:
    Long Island, NY
    A lot of people are real hesitant about having a radar mounted in front of their crotch. Something to consider. Installing it on a mast is also an option. Depending on the style boat you have there are all sorts of arches & masts that can look very good. They also give you the ability to mount other things like TV domes, speakers & VHF antennas. The higher you go the better reception and send ability you have (a nice thing in rough seas). You can have it hinged if height clearance is a concern.
    K1W1 makes a very good point. I've watched the birds on more than a few boats I've moved. Wedges made of starboard work very well and are easy to make.
  4. DaddysGirls

    DaddysGirls New Member

    Joined:
    Sep 25, 2010
    Messages:
    16
    Location:
    Longport NJ
    This is all great info guys... thank you

  5. CatTech

    CatTech New Member

    Joined:
    Sep 28, 2010
    Messages:
    56
    Location:
    south FL
    I have been on sea trials where the electronics installers have measured the angle of the proposed location at cruise speed to determine the best angle to fabricate the wedge.
  6. DaddysGirls

    DaddysGirls New Member

    Joined:
    Sep 25, 2010
    Messages:
    16
    Location:
    Longport NJ
    Is it true if the radar is mounted on the front of the flying bridge by the windshield all you get is forward radar view? Basically 180 degrees ? The radar doesn't go through the bridge?
  7. NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,214
    Location:
    Long Island, NY
    Not necessarily true. It all depends what (metal mostly) that you have there. Generally though no problem except that you'll have it in your crotch. :eek: Of course that would rarely be an open array as that takes more room to spin.
  8. NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,214
    Location:
    Long Island, NY
    Painting a radar dome

    I've been getting mixed advice about painting a radar dome. The concensus seems to be that there's no problem if done right (not too thick and using non-metalic paints), but our painter is adamently against it. Needless to say I won't have this painter leave his comfort zone. However, I'd like to hear from owners or captains who have actually had their domes or arrays painted to learn from their experience. Did it result in any loss of signal, and what type of paint did you use? Thanks.
  9. Navatech

    Navatech New Member

    Joined:
    Mar 27, 2013
    Messages:
    89
    Location:
    Hollywood, FL
    I'm not sure installing a source of electromagnetic radiation at "family jewels" height is a good idea...

    In fact, back when I was in the navy it was forbidden to even approach the working radar... And, getting hit by the array was only one of the reasons given...
  10. Navatech

    Navatech New Member

    Joined:
    Mar 27, 2013
    Messages:
    89
    Location:
    Hollywood, FL
    Again, referring to my navy background, yes you can paint the radome... HOWEVER, it should be done with special paint...

    If you want to be safe my suggestion is to contact the manufacturer's tech support...
  11. triggerfish23

    triggerfish23 Member

    Joined:
    Jan 19, 2012
    Messages:
    43
    Location:
    Seattle, WA
    I've seen domes painted before, but I don't know with what. I'm with navatech. If you call the manufacturer of the RADAR I would think they would have some advice on safe products. I'm guessing it's out of the warranty period, but they'll probably advise that it will nullify it.

    Please let us know what you find out. I've thought about painting mine several times, but never followed up.
  12. HTMO9

    HTMO9 Senior Member

    Joined:
    Jan 13, 2009
    Messages:
    1,519
    Location:
    Germany
    Radar mount

    Most or all of the questions can be answered by remembering the principles of RADAR.

    Antenna height: As radar transmissions are of highest frequency (Giga Band) they are tranmitted true line of sight. Due to the shape of the earth, at sea, the horizon at 3 feet above the water (a man sitting in its rubber boat) is only about 2.2 NM away from his position. So, the higher, the better. A 72 NM range capable radar mounted 10 feet or less above the water is pretty useless. Plus any obstacle blocks transmission. A tinted windsrcreen for example can be a perfect radar deflector.

    The vertical beam width of a typical pleasure craft radar is about 25 degree. When a planning craft is running nose high on the plane, it is easy to calculate, when the radar is looking for birds rather than obstacles at sea. If you want perfect radar performance both at low and high speed, the easiest answer is an adjustable radar mount. Set to level when at displacement speed and nose down at planning speed. There are gimbled mounts for radom antennas on the market, where oil dampend radar mounts level automatically in pitch and/or roll by gravity (very common with sail boats) or are manually adjusted by hand.

    Danger of radar transmissions: Also a typical pleasure boat radar consumes only a few watt, it transmits pulsed power. A 4 KW radar is transmitting pulsed electromagnetic power in a magnitude, any microwave stove would be proud of. The antenna position therefore should be definately away from the famous "family juwels" or a human brain (cancer). The only work around procedure, if for any reason the antenna has to be mounted at bridge level, is the use of an broadband radar (i.e. Simrad 4G). This type of antenna transmits power in the magnitude of a cellphone at max transmitting power. These type of radars have an excellent resolution at lower range but loose against normal radars at greater range than 25 NM.

    Painting the radom: The normal pleasure boat radom is made of plastic material which minimizes the loss of electromagnetic power passing through. But there are losses. Thats why an open array always performes better than a radom type antenna. Painting will always degrade performance. Remember, the beam has to pass the radom twice and the electromagnetic power dissolves by 8th potency on its way to the reflector and on its return. As normal paint only degrades performance, metallic paint will block the radiation. And a thick layer of metallic paint will turn your radom into a cage of Faraday. It will not only block the radiation, it will heat up the antenna and will finally destroy it (like putting a metal plate in a microwave).

    My advice would be, if you want no radar mast on your boat high anough above your cockpit, buy a small removable radar support with a broadband radar and take it away when not needed.

    Cheers
  13. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    10,060
    Location:
    Satsuma, FL
    Our only attempt had been with a RayMarine 10kw ,6' array. We scrubbed the heck out of of the plastic and it looked near new. Then used normal vinyl letters with our ships name and are very happy with our results.
    Paint on the array was a concern but after a lot of scrubbing I thought I'd won the lotto. The factory label was gone in no time and we get questioned on our custom array at every dock.
    Does your array or radome really need paint or some scrubbing effort. You may be surprised how well it will look and avoid any question of paint degradation issues.
    ,rc
  14. NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,214
    Location:
    Long Island, NY
    We could probably live with the Furuno lable, but the blue base is really a standout. We'd like to convert everything on the brow to the color of the brow.
    We've gotten the technical info, which says It can be done, but tight now we're looking for first hand experience.
  15. Navatech

    Navatech New Member

    Joined:
    Mar 27, 2013
    Messages:
    89
    Location:
    Hollywood, FL
    Painting the base (as opposed to the array/dome) is not an issue... Just paint it if that's what you want to do... It won't affect the radar performance...

    I hope they recommended a paint...

    As I said, back in the navy they'd do it quite regularly... No problems as long as you used the right paint...