Picking a PC and GPS for marine navigation

Could you recommend a netbook or slate computer that has built in GPS for offshore navigation? The boat already has a Garmin GPS giving position and speed only: no charting. I need the PC to run OpenCPN with a selection of nautical charts, but also have a good battery life and a reasonably quick battery charge time.
Paul O Donovan
There are quite a few Windows PCs and slates with GPS (Global Positioning Satellite) chips built in, but these are mostly aimed at the commercial and industrial markets, and they are often ruggedised. Examples include Panasonic Toughbooks such as the CF-U1 or CF-H2.

Boating GPS
Typical users include field workers and service technicians, health services, police forces and the military. However, you can get better value by buying a standard PC or netbook and adding a GPS either on a Mini-PCI Express card such as the Sierra Wireless MC8781, or via a dongle that fits a USB slot, such as the Navisys models. In fact, if your Garmin GPS receiver can output NMEA 0183 data, you should be able to connect that to a PC. (NMEA is the National Marine Electronics Association.)

Either way, the GlobalSat BU-353 WaterProof USB GPS Receiver (SiRF Star III) looks like the sort of thing you need. It’s small, waterproof, has a magnetic mounting and comes with a 5ft cable, so you can position it where it will get a good signal while using the PC in a more sheltered position. Performance should be much better than the sort of GPS typically built into mobile phones and media tablets, often to meet America’s E911 laws.

When it comes to choosing a PC, you will have to find the right balance between screen size, speed, battery life and price. The cheapest option is a netbook such as Asus Eee PC 1015PX, which has a 10.1in screen and a 1.5GHz Intel Atom N570. I’d suggest limiting your netbook hunt to the N550 and N570 as these are both dual-core Atoms with low power requirements. If you are willing to trade performance for battery life, look at netbooks with single-core N270, N280, or Z530/Z540/Z550 chips instead.

The drawbacks with netbooks may include limited 1GB memory, the use of Windows 7 Starter, and limited screen resolutions. You can easily upgrade the memory to 2GB for about £14. You can easily do an in-place upgrade to Windows 7 Home Premium, if you need to, or you could install a free version of Linux alongside it. However, you can’t fix the 1024 x 600 screen resolution, which might be a bit cramped for charts and maps. It will cost more to buy something with a standard 1366 x 768 pixel screens.

If buying a laptop instead of a netbook, the best compromise for price/performance/battery life is the 1.33GHz Intel Core i3-380UM, where the UM designates an ultra-low-power-consumption version of the mobile processor. Typical models include the Acer Aspire TimelineX 1830T, Lenovo ThinkPad Edge 11 (NVY5FUK), and the touch-screen Fujitsu Lifebook T580. If you want something cheaper, a laptop based on the older Intel Core 2 Duo S9300 or similar chip would do. If you want something faster, then there are several i5 options such as the 1.3GHz i5-560UM and 470UM. There are also some new Ivy Bridge Core iX processors on the way in Ultrabooks such as the Asus UX21 and UX31. These use smaller, faster versions of the current Sandy Bridge chips.

Lots of PCs now claim a battery life of six hours to about 11 hours (with Wi-Fi and Bluetooth turned off), and you can double that just by buying a spare battery. Put the PC into hibernation and you can swap the batteries in 15 seconds or fewer. However, bear in mind that battery performance decays with use, and after a couple of years, your eight-hour battery could be flat in less than half the time.

You can run OpenCPN on a window or Linux PC or a Mac, so you could also consider a MacBook Air, if it also runs other software you need. However, you may also want to use alternative charting systems such as Maptech‘s Chart Navigator Pro or Memory Map, which are not available for Mac OS X.

Another alternative would be an Apple iPad 2, because the GPS version includes a tiny Broadcom BCM4750 GPS chip “designed to interface with host processors in mobile phones, PDAs, personal navigation devices, and MP3 players”. (That is, it uses the device’s processor and memory to do most of the work.)

I suspect that the open source OpenCPN won’t run on the iPad because it would have to be completely rewritten in Objective C. However, you could use iNavX on an iPad, assuming you can get charts that you like. The web page says that you can’t use the charts you have on your PC: iNavX downloads charts directly from a chart server, however many of the charts and maps available at x-traverse can also be used on a PC or Mac. X-traverse offers Navionics 28XG UK – Ireland – Holland – iPad – 2011 edition for $68.99.

Also, if you have Memory-Map on a PC, you can send maps to an Apple iPhone or iPad, if you buy the corresponding app. Memory-Map is based in the UK and offers UK & Ireland Marine charts. It is now developing an Android app.

There are also some Navionics maps for Android that work without an active internet connection. Obviously you have to avoid GPS-based systems that download maps on the fly, because you generally won’t have an internet connection.

GPS has yet to become ubiquitous. However, it seems to me that the toughening up of E911 location requirements and the arrival of cheapish chips like the Broadcom BCM4750 will lead to GPS appearing in many more gadgets, and probably in most devices that have a mobile phone connection. Eventually, most 3G dongles could include GPS as well.