Nearest Light for Windows


This program no longer works and has been retired in favor of the phone/tablet apps which are much better. This information is being kept for those who may still be using it.

Nearest Light finds the closest lights to your current position, whether live from GPS or from a manually entered position, within the range specified.  The data comes from weekly XML updates provided to the Light List by the United States Coast Guard.  Nearest Light will automatically check online for updates when starting, if there is an internet connection.  Be sure to update Nearest Light prior to going out on the water for any surveys.

NL Setup

NL Light List

The program only alerts you monthly, so if you want the latest weekly update, force an update by selecting “None” and then re-select your district in the Setup tab.



  1. When starting NearestLight, load the light list first in the Setup tab, before going to the LightList tab.  Select your district from the map.  It may take up to *10 minutes* to download the light list since the USCG server seems to be throttled – please wait.  If USCG changes XML file locations, you may need to manually locate and download the file, and choose the Use File (advanced) option.
  2. Choose either a fixed position (useful for armchair planning) or GPS.  Note the latter will put you where you are (d’oh), which may be a long way from the coast if you live inland!
  3. Enter a range in nm to find the lights within that distance from the fixed position or GPS.
  4. If changing the range, or lat/lon for a fixed position, the background will turn color while editing.  After a couple of seconds with no changes, it turns back to white, and the database search begins.  This may take several seconds on a netbook so wait for it.  You may print the light list table, but the print capability is rudimentary – you may need to adjust the font size downward to 9 or 8 to get most of the table fields.  When the printer dialog comes up, select your printer and then set your printer preferences to Landscape mode before printing.
  5. F1, F2, F3 are keyboard shortcuts to the Setup, LightList, and About tabs.
  6. NearestLight is found under Start, Programs, USPS Clint O’Connor E228579 – you may want to create a shortcut on the Desktop for NearestLight.  Right-click on NearestLight, Send To, Desktop.


  • Notebook or netbook running Windows 7 or Vista (XP appears to work for this program)
  • External USB GPS receiver and driver
    • Generally, any GPS unit with a serial interface will work, whether it is a USB GPS with a built-in USB-serial interface, or a serial GPS with an external USB-serial adapter.  For navigational accuracy, it should be WAAS-enabled.  Specific units known to work with netbooks and Windows 7 are:
      • Generic USB GPS Receiver
      • Garmin GPSMAP 76 with Garmin serial cable and Keyspan USB-serial adapter
      • US GlobalSat BU-353 Waterproof WAAS Enabled USB GPS Receiver (,
      • US GlobalSat MR-350P Bulkhead-mount WAAS Enabled serial GPS Receiver – requires USB cable set adapter (
      • Note that Garmin uses a proprietary format and the Garmin 18 USB “hockey puck” does not work.  A Garmin 76-series using a serial cable and a USB-serial adapter does work, with the output configured to NMEA 4800.
    • Windows 7 will automatically find the latest driver for some serial adapters, including the USGlobalSat devices, if online.  Try plugging it in first before using the driver that comes with it.


The releases use ClickOnce technology developed by Microsoft.  What this means is, after you have initially downloaded one of these programs, every time you start the program, it will automatically check online to see if there is an update.  If you are not online, it will run the version currently on your computer.

If you are online and there is an update, it will ask you if you want the update, and assuming you do, it will automatically update to the newest version released and then run the program.