Lowrance electronic globalmap baja 840c 用户手册

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GlobalMap Baja to determine direction of travel, you must be moving 

and the faster, the better. This is not to say that it won’t work at walk-

ing or trolling speeds — it will. There will simply be more "wandering" 

of the data shown on the display. 
GPS is plenty accurate for route navigation, but the U.S. Federal Avia-

tion Administration has special needs for aircraft traffic control that go 

beyond basic GPS. The FAA has a program to boost GPS performance 

even further with its Wide Area Augmentation System, or WAAS. This 

GPS add-on will include a time control element that will help airliners 

fly closer together while avoiding collisions. In addition to carefully 

spacing airplanes along travel corridors, WAAS will eventually make 

instrument landings and takeoffs more accurate as it replaces existing 

aviation navigation systems. 
Non-aviators can use WAAS signals to make their GPS navigation even 

more accurate. Your unit receives both GPS and WAAS signals. How-

ever, WAAS has some limits you should know about. 

WAAS can boost the accuracy of land GPS navigation, but the system 

is designed for aircraft. The satellites are in a fixed orbit around the 

Equator, so they appear very low in the sky to someone on the ground 

in North America. Aircraft and vessels on open water can get consis-

tently good WAAS reception, but terrain, foliage or even large man-made 

structures frequently block the WAAS signal from ground receivers. 
You'll find that using your GPS receiver is both easy and amazingly 

accurate. It’s easily the most accurate method of electronic navigation 

available to the general public today. Remember, however, that this 

receiver is only a tool. Always have another method of navigation avail-

able, such as a map or chart and a compass. 
Also remember that this unit will always show navigation information 

in the shortest line from your present position to a waypoint, regardless 

of terrain! It only calculates position, it can’t know what’s between you 

and your destination, for example. It’s up to you to safely navigate 

around obstacles, no matter how you’re using this product. 

Many instructions are listed as numbered steps. The keypad and arrow 

"keystrokes" appear as boldface type. So, if you're in a real hurry (or 

just need a reminder), you can skim the instructions and pick out what 

menu command to use by finding the boldface command text. The fol-

lowing paragraphs explain how to interpret the text formatting for 

those commands and other instructions: