The Bassholes - It takes one to know one.

The Global Positioning Systems Basics
on Tuesday 01 December 2009
by Ken Sturdivant

The Global Positioning Systems Basics

The G P S units are simply a hand held electronic compass with a memory.

The lakes around the south are lower than normal from a three year drought. With little rain expected until early next year now is the time to head to your favorite lake with a camera and a hand held Global Positioning unit. Want to fish where the fish live eleven months of the year? Now is the time to find great locations and log the lakes. The G P S units are light and will fit in a shirt pocket. These tiny receivers will now take you back to the road bed, the humps or the brush piles on the lake with amazing accuracy.

The Global Positioning Systems use satellites that are maintained by the United States Department of Defense. These satellites have been in outer space since 1970 to provide accurate, reliable and continuous position reporting. This system is available 24 hours a day and can be used on land, sea and air. The signal is unaffected by weather.

There are 24 satellites that are 11,500 miles above the earth and their movements are in a precisely controlled orbit. The satellites circle the earth every 12 hours.

Global Positioning Systems are affected by the surrounding terrain. Sharp angles such as rock ledges and mountains can affect this unit. Heavy tree cover can also affect this system. Global Positioning Systems today will allow the user to find any location in the world.

The Global Positioning Systems today lock on to as many as 8 to 12 satellites. Only three are needed to fix your position. If the unit has an altitude feature, four satellites are required. Do not be concerned on how many satellites you have. These current units are called parallel channel receivers.

Speed can be measured as close as one tenth of a mile per hour.

The Global Positioning units will get you as close as 20 feet back to the location you originally marked. These units are easy to use and come in either a mapping unit or plotting unit.

Now for the angler, here is how to use GPS.

Many sonar units have a built in GPS receiver. In order to use this GPS technology, think of the GPS as a marker buoy (or electronic marker). When you throw a marker buoy, you “marked” that spot. Hit the waypoint save button twice and you just put that marker or spot in the unit. You also created a file for that spot with: DATE, TIME GPS DATA, AND A NUMBER.

Now to recall that waypoint, hit the waypoint button once. Now you will see saved or new. Hit save and then enter and the numbers will pop up with all the waypoints you saved so far. Call one up and then GO TO. The unit will add a red line from where you are to the waypoint.

Always save the ramp where you launched. If it gets dark, foggy or you get completely turned around, the GPS will get you back to the ramp. Also, learn to use a hand held compass while using the GPS. In case the GPS fails, you can then go back to basics with the compass.

BACK UP YOUR GPS FILES! You do not want to loose that data. Write every waypoint down and put it away or transfer the date to a black chip from the GPS unit.

Lowrance and Navionics sell MMC or Memory cards you can add to your units to get more “detailed mapping”. Check out the MMC cards at or Be sure to tell the GPS to read the mapping card by going into the MAP DATA. If you do not tell the machine to read the card, it will not tread in automatically. E mail me for any further details.

For the money, it's worth it to get the mapping unit. These web sites have additional detailed information on the Global Positioning Systems. See for a tutorial