The Delorme Earthmate (shown docked in the optional PowerPack) is a compact GPS receiver that works with your PDA or laptop computer. And with their larger screens and greater computing power compared to a typical GPS receiver, it makes a superior combination for trip navigation.

The Delorme Earthmate GPS device measures only 1 7/8" W x 2 3/32" H x 13/16" D, but it's just as accurate as a larger unit. The Earthmate has a standard 12-channel receiver that's Wide Area Augmentation System (WAAS) capable. WAAS makes possible a position accuracy to within three meters. The receiver is also National Marine Electronic Association (NMEA) compliant, which means it can send navigation data to boating instruments like autopilots and chartplotters and other accessories.

If you use the Earthmate receiver with a laptop, it connects to the computer's USB port with the supplied 6-foot cable. If your laptop has a serial port instead of USB, an optional serial cable is available. The receiver runs off the laptop's battery but uses very little power. Once plugged in, its indicator light will quickly move through three stages. The LED will glow red while searching for GPS satellites, yellow when it finds two, and then green when it locks onto three or more satellite signals.

The Delorme Earthmate also works with Palm OS handheld computers and Pocket PCs. When used with a PDA, unlike laptops, the receiver requires a separate power source. Delorme offers the PowerPack which docks onto the Earthmate and uses four AAA batteries to supply the power. The PowerPack also has a cigarette lighter power adapter as a substitute for the internal batteries. Data transfer is handled with a cable specific to your PDA or a serial cable for older units.

If the thought of one or more connector cables is more than you want to deal with, there is an alternative. Delorme also makes the PowerPack in a wireless version. It uses Bluetooth technology to communicate with a Bluetooth enabled laptop or PDA. This lets you freely position the Earthmate where it can get the best satellite reception and place the computer where it's most convenient to operate. This means the receiver could be at one end of the vehicle and the computer at the other. The Bluetooth PowerPack can also be used with a cable for non-Bluetooth computers.

Both PowerPacks will work with a rechargeable lithium ion battery. The lithium battery can be be recharged while in the PowerPack using either the supplied AC charger or off a vehicle's battery using the cigarette lighter power adapter. This rechargeable battery pack comes with the Bluetooth PowerPack and is optional for the non-Bluetooth version. Both PowerPacks also have an on/off switch.

Whether you get a Delorme Earthmate GPS receiver with or without a PowerPack, certain features come standard. Included with the receiver is a current version of the Street Atlas USA or Topo USA map program. This map software provides detailed real-time guidance for city or off-road trips. You can print out the maps to navigate by or give voice commands to the receiver and receive back vocal prompts for making each turn. Other Delorme software will also work with the Earthmate as will third-party mapping software if the proper driver is available.