GPS for Dummies.pdf - Engineering Surveyor

66Part II: All About GPSInternal memoryA receiver’s internal memory holds such data as waypoints, track logs, routes,and uploadable digital maps (if the model supports them). The more memorythe receiver has, the more data you can store in it. All the data that’s beenstored in the GPS receiver is retained when the device is turned off.GPS receivers have different amounts of memory. Unlike personal computers,you can’t add memory chips to a GPS unit to expand its internal memory.External storageSome GPS receivers aren’t limited to internal memory for storage, usingsupport memory cards that can be plugged into the receiver to store data.External memory can be either Manufacturer proprietary data cards Generic (and less expensive) storage, such as• MultiMediaCard (MMC; www.mmca.org)• Secure Digital (SD; www.sandisk.com)Accessory programsMany GPS receivers have built-in accessory programs that display varioushandy features such as Calendars with the best time to hunt and fish Sunrise, moonrise, sunset, and moonset tables Tide tables Calculators GamesUser interface modesSome GPS receivers have simple and advanced user interface modes.