Page 3 of 3 FirstFirst 123
Results 21 to 30 of 30
  1. #21
    Join Date
    Nov 2009
    Location
    Home UK Midlands / Boat Croatia
    Posts
    19,432

    Default Re: Radar reflector in 'landscape' orientation

    Quote Originally Posted by alan_d View Post
    As I recall, the Canute story was about the futility of resisting the forces of nature rather than anything man-made. "The onward march of progress" is one of these stirring phrases beloved of politicians and other orators which when closely examined turns out to mean very little, except that the speaker approves of the change they are referring to.
    I haven't got a dog in this particular fight but, as I said before, watch this space.

    Richard

  2. #22
    Join Date
    May 2005
    Location
    up on the moors.
    Posts
    33,293

    Default Re: Radar reflector in 'landscape' orientation

    Not sure I understand that, Thistle. If all the reflecting surfaces are at 90 degrees to each other, doesn't the horizontal circle of a normal reflector become the vertical circle, and vice versa ?

    Ooops, IF, IF, IF.

    (I am still trying to find an old Cyclops reflector.)
    I think, therefore I am. I am, therefore I sail.

  3. #23
    Join Date
    Jun 2005
    Location
    Solent, UK
    Posts
    4,610

    Default Re: Radar reflector in 'landscape' orientation

    This only applies to the simple corner reflectors formed by two flat plates at 90 degrees to each other giving eight “corners” . Stacked arrays are (in theory anyway) a number of single “corners” arranged at different planar orientations around the vertical axis of the array, if fired horizontally, they would only give a return at 90 degrees to the axis of the array, not “all round”.
    Grow old disgracefully, it's more fun

  4. #24
    Join Date
    Jun 2019
    Location
    Tynemouth
    Posts
    277

    Default Re: Radar reflector in 'landscape' orientation

    Quote Originally Posted by Topcat47 View Post
    AIS and Seeme both need good, reliable supply of electricity all the way to the top of the mast from the battery. Not a problem on a modern TSDY, I’d suggest but not necessarily so on a small cruising yacht. I have had my masthead tricolour die mid channel due to water ingress by the deck plug, but at least I knew when it occurred. I cannot quite bring myself to wholly rely on an electronic gizmo which may or may not be working ( how would you ever know ?). IMO a
    good Passive reflector is always “on”. Anything else is belt & braces.
    Yes a fair point about the power supply.
    I would respectfully point out that neither needs its aerial at the top of the mast to be useful.
    The Echomax has little LEDs on the switch above the chart table, which tell you if it's working.
    I would guess that AIS gizmos are smart enough to alert you if they go wrong?
    Last edited by Ohlin Karcher; 17-07-19 at 07:48.

  5. #25
    Join Date
    Aug 2003
    Location
    Chichester
    Posts
    401

    Default Re: Radar reflector in 'landscape' orientation

    Quote Originally Posted by RichardS View Post
    All ships have radar .... but all ships have AIS and so do many other boats, many of which would terminate your existence in a collision.

    Ships do use AIS for collision avoidance provided that you have a transmitter and once you have a transmitter you can use it for things other than collision avoidance, unlike an Echomax which is a one-trick pony.

    A number of port authorities have now introduced legislation which makes AIS compulsory for all boats. That trend will continue until such time as AIS is the dominant collision avoidance mechanism. Watch this space.

    Richard
    I'm not sure I want to totally rely on a collision avoidance system that depends on the other person setting up their system correctly. I always have ais targets that are thousands of miles away because the gps co-ordinates have not been entered. Who is to say what other data might be incorrect.
    At least with radar, interpretation of the risks is down to me.

  6. #26
    Join Date
    Jun 2009
    Location
    From the Needles to the Nab, from Cowes to St Catherine's
    Posts
    4,784

    Default Re: Radar reflector in 'landscape' orientation

    Not forgetting that some ship's displays have the option to stop showing class B transponders....
    Substance over style

  7. #27
    Join Date
    Nov 2009
    Location
    Home UK Midlands / Boat Croatia
    Posts
    19,432

    Default Re: Radar reflector in 'landscape' orientation

    Quote Originally Posted by lumphammer View Post
    I'm not sure I want to totally rely on a collision avoidance system that depends on the other person setting up their system correctly. I always have ais targets that are thousands of miles away because the gps co-ordinates have not been entered. Who is to say what other data might be incorrect.
    At least with radar, interpretation of the risks is down to me.
    Why would one ever need to enter GPS co-ordinates into an AIS transceiver?

    Richard

  8. #28
    Join Date
    Nov 2007
    Location
    Cascais, Portugal
    Posts
    983

    Default Re: Radar reflector in 'landscape' orientation

    Quote Originally Posted by lumphammer View Post
    I'm not sure I want to totally rely on a collision avoidance system that depends on the other person setting up their system correctly. I always have ais targets that are thousands of miles away because the gps co-ordinates have not been entered. Who is to say what other data might be incorrect.
    At least with radar, interpretation of the risks is down to me.
    I understood that AIS transponders required a dedicated GPS feed, rather than taking a feed from a separate system (mine certainly does), so I'm not sure how 'gps coordinates have not have been entered'. Certainly some class A data is manually added (ships destination etc), but the important stuff is automatically input.

  9. #29
    Join Date
    Dec 2003
    Posts
    5,441

    Default Re: Radar reflector in 'landscape' orientation

    Quote Originally Posted by neil1967 View Post
    I understood that AIS transponders required a dedicated GPS feed, rather than taking a feed from a separate system (mine certainly does), so I'm not sure how 'gps coordinates have not have been entered'. Certainly some class A data is manually added (ships destination etc), but the important stuff is automatically input.
    You understood correctly!

  10. #30
    Join Date
    May 2007
    Posts
    37,296

    Default Re: Radar reflector in 'landscape' orientation

    You do get the odd AIS signal with a clearly duff position.
    Big ship AIS will (sometimes) have the ability to take a position from another nav system.
    Your own AIS receiver needs a good GPS signal to work out relative positions.

Page 3 of 3 FirstFirst 123

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Latest YBW News

Find Boats For Sale

to
to