I have it..not very useful..its just an instructional video for Raymarine radars (older ones)...take a power squadron course or starpath ...probably instructions from a radar manual will serve you just as well.If you already have a radar,use it in daylight and good viz adjusting range, gain and clutter till your confident ..Try the EBL,electronic bearing line on targets to determine collision risk..a great tool for the best time to be on the water...at night. good luck.