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(Huntingtown, MD) It is possible to identify an in-transit ship as the most likely source of FSI (Foreign Shipping Interference) in the GMRS (General Mobile Radio Service.) Using an AIS - Automatic Identification System receiver and a directional antenna the signal from ship’s AIS transponder will tell you the ship’s name, it’s ITU MMSI registration, call sign, country of registration and destination. Using the MMSI look up at the ITU you can determine what company owns the ship.
On the Chesapeake Bay near Plum Point, MD the PopularWireless AIS receiver has so far identified three ships using GMRS channels while in US waters. Vessels from Norway, Vanuatu, and Singapore are currently on the Foreign Shipping Interference Log. The Norwegian vessel was docked and easily identified with a directional Yagi antenna at some twelve miles distant. The ships from Vanuatu and Singapore passed PopularWireless on the Chesapeake Bay and each was followed with the directional antenna as they sailed by.
The requirements are pretty simple but there is an investment in equipment. The first AIS receiver was an ICOM IC-R8500 receiver. A wide variety of inexpensive scanner receivers can be used as long as the one selected can be modified to take audio directly from the radio discriminator. The receiver was changed that to an SR-161 AIS receiver purchased for $189 from Milltech Marine. The power requirements are very low. An older three-amp power supply was used successfully. The antenna is a VHF antenna with LMR400 cable at about 60 feet above sea level and of course the higher the better. Use good low-loss feed line. The SR-161 serial data from is connected to a computer with Ship Plotter software installed. The switch to serial data from an audio feed to the sound card restored another analog audio input on the computer used for recording ship transmissions on the unauthorized channels also via the ICOM R-8500. The ShipPlotter software is about $30. The payment is processed in Europe so the price is up and down a bit based on the current exchange rate.
Using the ShipPlotter software you can super impose the ship on marine navigation charts or photographs from Google Earth. It is possible to zoom in on a chart to determine where a ship is berthed or moored. A bearing from the chart to your location can be compared to the bearing determined from the directional antenna. ShipPlotter has an active Yahoo Group where the program author and active users provide some support for users of the software. It is even possible for a group of licensees to create their own server and share local data using this product.
Now if you don’t have the cash to purchase an AIS receiver you can purchase the AIS software at Shipplotter.com and watch the feeds from various ports around the United States. There are many ShipPlotter users sending regular data on many US ports that a GMRS licensee could use to help identify Foreign Shipping Interference from a ship illegally using GMRS channels in US waters. Ports in Delaware, Virginia, Texas, California, Washington, and even the Great Lakes are covered. Licensees will also find that many other websites that display AIS ship data on line. Another good one is ShipPlotting.com.
Once the name and owner of the ship is known the GMRS licensee can attempt to contact the ship owner directly by email or mail. My first attempt to contact a ship owner in Singapore was unsuccessful. This did not surprise me given the lack of cooperation from ship’s Captains I have encountered on both coasts. Should the licensee be unsuccessful, a Personal Radio Association GMRS Interference form can be completed (available at PRAWEB.ORG) and sent to the FCC GMRS address in Gettysburg (See Part 95) directly or through the PRA along with the AIS data and the directional methods used to verify the source of the radio signals was the ship in question.
Licensees curious what ships are in or around the area of Southern Maryland can check the AIS Map of the Chesapeake Bay generated at PopularWireless HQ through the courtesy of Shipplotter AIS software and unique scripts written by Shipplotting.com.
At PopularWireless two ICOM-R8500’s and one RadioShack PRO-2006 monitor GMRS, FRS, and international shipping frequencies to assist in the identification of FSI. On any complaint audio files can be recorded and sent to the offending company as evidence. All three scanners are controlled by Spectrum Manager, a ScanStar product. Spectrum Manager is an outstanding product and is very useful for this purpose. A PC audio card conversion to the M-Audio Delta 1010LT purchased from SweetWater will allow recording up to eight computer controlled radio receivers.
