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Look Angle Instructions

These instructions use the Look Angle Tables to determine where to point the antenna to receive the NOAAPORT signals. The results of these instructions will be azimuth and elevation angles. [Azimuth = degrees from true North. Elevation = degrees above horizontal.]

  1. Determine your receiver's location (Latitude and Longitude). You can use either the Cities List or ask a local surveyor.
  2. Determine the latitude difference (delta Lat.) between the receiver's latitude and the satellite's latitude (always zero).
    Example:
    Receiver 
    Latitude = 27ºN
    Satellite Latitude = 0º
    Difference 
    = 27º
  3. Determine the longitude difference (delta Long.) between the receiver's longitude and the satellite's longitude (101º W for NOAAPORT).
    Example A:
    Receiver Longitude = 140º W
    Satellite 
    Longitude = 101ºW
    Difference = 39º
    Example B:
    Receiver 
    Longitude = 220ºE (360-220=140)
    Satellite Longitude = 101ºW
    Difference 
    = 39º
  4. Read down the table column for the delta Longitude and across the table row for the delta Latitude to the point of intersection. You will find two values listed.
  5. The lower line is the elevation angle (the angle above horizontal) for the antenna.
  6. The top line is an Azimuth factor. You need to make a few more additions or subtractions.
    • If the receiver is in the Northern hemisphere and the satellite is to the East of the receiver, Add the factor to 90º to get the correct azimuth (90º + factor = azimuth).
    • If the receiver is in the Northern hemisphere and the satellite is to the West of the receiver, Subtract the factor from 270º (270º - factor = azimuth).
    • If the receiver is in the Southern hemisphere and the satellite is to the East of the receiver, Subtract the factor from 90º to get the correct azimuth (90º - factor = azimuth).
    • If the receiver is in the Southern hemisphere and the satellite is to the West of the receiver, Add the factor to 270º (270º + factor = azimuth).


    [Satellite Location]




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