In a case the size of a fat cell phone, the Garmin GPSMAP 76CS has about everything you could want in a GPS handheld. Besides standard GPS features, it includes a barometric altimeter, an electronic compass, huge internal map storage, geocache logging and a set of GPS games. And all of this is displayed on a high-resolution color screen.

The value of the Garmin 76CS begins with its Americas basemap which has auto-routing capabilities and U.S. tide data, including tide prediction stations. For loading more detailed maps, it has 115 MB of internal memory and a USB connection for fast transfers from your PC. This lets you choose from a wide selection of map data including Garmin's BlueChart marine charts, U.S. Topo 24K or City Select land maps. Up to 1000 waypoints can be entered and identified with names and symbols. Editing is easy using the onscreen menu system and the large directional keypad.

A 256-color LCD, 2.6" (diagonal) screen is used for presenting the text and images of the Garmin 76CS. The display's brightness, contrast and range of colors make readings in full sunlight no problem. And it's the same at night, since the display, as well as the entry keys, have adjustable backlighting. There's also a option to display text extra large for even easier viewing.

To achieve maximum positional accuracy, Garmin's GPSMAP 76CS is Wide Area Augmentation System (WAAS) and Differential GPS (DGPS) ready. And when WAAS signals are received, the position calculations are made with an error of less than three meters 95% of the time.

Even though the 76CS GPS receiver can give very accurate position information, GPS receivers have two navigation problems. The first problem is that GPS elevation readings aren't as accurate as horizontal position readings. So to overcome this drawback, Gamin built a barometric altimeter into the 76CS. It's accurate to within 10 feet and has a resolution of 1 foot. In addition to the current elevation, the rate of ascent/descent, a profile of elevation over distance or time, or pressure changes over time, may be displayed.

The second problem the Garmin 76CS receiver overcomes is an inherent GPS directional shortcoming. GPS can only show your direction when you're moving. If you stop moving, GPS can locate where you are, but can't show what direction you're heading. You resolve this with either a mechanical compass, or like Garmin did, with an electronic compass as part of the receiver. The compass has an accuracy to within five degrees and a one degree resolution.

To increase the versatility of the Garmin GPSMAP 76CS, it has a serial port to connect to equipment using National Marine Electronics Association (NMEA) protocols. This includes autopilots, plotters and repeaters. For instance, this would let you hook up a sonar unit to the 76CS and have it sound an alert to warn you when you're in shallow water. With the built-in celestial tables for best fishing times, you would be all set to get out on the water.

Map display features of the Garmin 76CS receiver include selectable coordinates and the ability to convert loran fixes to GPS readings. For concise readings about your progress along a route, there's a trip computer which shows such things as current, average, and maximum speed, and an odometer for distance traveled. And you can set audible alarms to alert for getting off course, dragging your mooring, or nearing specified waypoints. The receiver saves your path every time you move, and it has memory available to store up to 20 of these tracks so you can retrace a previous path.