Updated Satphone Tricks for Pacific Ocean Races

Revised: Tuesday, May 13, 2014
Joe Buck
Updated Satphone Tricks  

	With a bit of planning before the race, you can use your Iridium satphone to get all of the data and weather information during the race that you could get using a broad(er)band Inmarsat Fleet Broadband terminal, e.g. Furuno FleetBroadband Satellite terminal or a KVH VSAT TracPhone. You can get the same data quickly and at much less expense without the weight, cost and power consumption of the broad(er) band equipment. The trick is to bypass downloading graphics data which is used only to search for, identify and select the text and weather data that you wish to download. Instead, use internet addresses ("URL's") stored as bookmarks in your browser or in "batch" files to directly access and download the desired data.  

	For example, a batch file (which might be named "get-buoys.bat") that contains the text (all in one line without quotes):

"wget.exe http://www.ndbc.noaa.gov/data/latest_obs/46026.txt http://www.ndbc.noaa.gov/data/latest_obs/46042.txt http://www.ndbc.noaa.gov/data/latest_obs/51000.txt
http://www.ndbc.noaa.gov/data/latest_obs/51100.txt"

will download the most recent wind and wave reports from the respective buoys located at 1) 18 nm west of San Francisco, 2) 27 nm WNW of Monterey, CA, 3) 34.7N 136.7W (mislabeled as 245 nm N.E. of Honolulu) and 4) 252 nm NE of Honolulu.  The data is downloaded and stored in individually labeled files within a few seconds after you have connected the satphone to the internet and double-clicked on the batch file.  Open these text filings using Wordpad instead of Notepad to avoid seeing one very long line of text.

	I will describe in more detail below how to create the batch files and how to obtain and install the free software called "wget.exe" that the batch files use to download the data.  If you prefer, you could download the same data using a bookmark for each of the addresses listed above, although using the browser requires multiple "clicks" and other steps to download and store the data from the buoys in the four files.  If you use a browser, be sure to configure the browser to open at blank page, otherwise the browser may take a long time, or may even get stuck, trying to download the opening page.  You also should configure the browser default to not download graphics.

	Spend some time at home "surfing the net" to identify the URL's of the text and weather data that you will want to download.  A good place to start is at: 

http://www.nws.noaa.gov/om/marine/internet.htm.  

Avoid addresses that include graphic interfaces, instead look for addresses ending in ".txt" such as
http://weather.noaa.gov/pub/data/raw/fz/fzhw60.phfo.off.hfo.txt 
which provides the forecast for the offshore waters of Hawaii in a text format. Http://www.ndbc.noaa.gov displays weather buoys throughout the world together with their respective numerical identification numbers for use in the batch file or bookmarks. http://weather.noaa.gov/fax/ptreyes.shtml displays a wide selection of weather maps. If you hover your cursor over one of the "TIF" icons, the URL for the map will appear (at least in Firefox) in the lower left corner of your browser. E.g., the 24 hr surface forecast, VT 00Z, for the Pacific from 18N-62N, East of 157W might be located at: http://weather.noaa.gov/pub/fax/PPBE00.TIF. 

Because each weathermap has a size of 25-30 kbytes in "TIF" format and a size of 50-60 kbytes in "GIF" format, be sure to select the "TIF" format. Also make sure that your computer has software for displaying maps that are in the "TIF" format. Check that the signal from the satellite is strong before attempting to download a 25-30 kbyte file. If the signal strength fades, the download may slow and you may even have to restart the process. I suspect that files of this size may be nearing the practical limit for downloads via the satphone. If necessary, you may avoid having to download a large GRIB file by, instead, requesting separate GRIB files for different geographical areas with different data grids and forecast times. If many boats are attempting downloads at the same time, you may have to try again at a less busy time. If Yellow-Brick provides tracking, you can connect the satphone to the internet, double-click the appropriate batch file, and download a text file containing the most recent position reports for 30 or so boats and then disconnect the satphone in less than a minute, often less than 30 seconds.

In a race to Cabo, I used a batch file named "get-boats.bat" that contained in a single line (without quotes): "wget.exe http://yb.tl/newport2cabo2013-expedition.txt --output-document=Scheds_yymmddhhmm.csv".

This batch file stores the updated boat positions in a file named "Scheds_yymmddhhmm.csv". After renaming the downloaded file to substitute the date and time of the report, I imported the file into Expedition to display the updated boat positions together with other information Expedition derived from these reports. For those of you not familiar with older Microsoft operating systems, a "batch" file is a text file containing a command line instruction, which filename ends with the extension ".bat". To create a batch file, use a text editor (Notepad) to create a text file containing, in a single line (without quotes), the desired command, e.g.: "wget.exe http://weather.noaa.gov/pub/fax/PPBE00.TIF" Then rename the file changing the ".txt" extension to ".bat". In order to display and change the file name extensions, in Windows 7 go to Start, Control Panel, Folder Options, View and then uncheck "hide extensions for known file types." You can obtain "wget.exe" from various sources, e.g., see http://noahcoad.com/post/614/using-wget-on-windows and http://gnuwin32.sourceforge.net/packages/wget.htm. Place all of the batch files together with wget.exe in the same directory or folder so that the command line in the batch file can locate and use "wget.exe". The downloaded files will be stored in this same folder. To obtain additional details on using wget.exe, in a terminal (command-prompt) window, "cd" to the folder in which you have placed wget.exe and type "wget.exe --help". In Windows 7, to access the command prompt, go to Start, in Search programs and files, type cmd.exe. Iridium provides software named "Direct Internet 3" for compressing data transfered from the internet to you via the satphone. However, it is my impression that such compression software is not very helpful here because the text files, e.g. buoy wind reports, boat position updates, etc. are relatively small in size and the weatherfax maps (in "TIF" format) and the GRIB files are already compressed so that any additional compression achieved by Direct Internet 3 is insignificant.

[Editor's note: use of the excellent Saildocs service also provides a means of getting graphics-free content, via email, either through your phone or other means]

Be sure to turn off all automatic updating for your (Windows) operating system and for all other installed software in your on board computer. Otherwise, when you connect to the internet via the satphone, the computer may attempt to download updates, which attempt would overwhelm the download capacity of your satphone. If someone attaches a photograph or other large file to an email that they attempt to send to you via the satphone, the large attachment will plug up and disable your email system. So for email, use sailmail.com which deletes all attachments (other than GRIB files) or use Winlink at which site you can specify limits on the size of any attachments, or take other steps to avoid large files or attachments such as setting up a new email address to be used only by trusted friends who will send only text files with no attachments. Instead of sending your position report via email, you might consider sending the report as an SMS text message. If the race committee uses a robot to acknowledge receipt of the SMS text report, your satphone will notify you when it receives the acknowledgment without your having to repeatedly connect to the internet to look for the race committee's email. You can try these tricks on your home computer that is already connected to the internet. Simply double-click on the appropriate batch file or browser bookmark and see how well it works. So, do your homework, enjoy fast and easy access to data via your satphone and have a good race. Joe Buck ( joeuhd@verizon.net)
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