Garmin GPSMap 640, hands-on #1

One gizmo that’s definitely coming along on the Gizmo delivery is this Garmin 640 beta unit.  In nüvi mode it can navigate the highways down to Connecticut, as it’s done well twice already, and I can then reboot it into marine mode for the voyage home, with XM audio and weather available all the while.  The marine satellite weather presentation seems particularly good, as you can see somewhat if you click on the screen above; it’s set up so that the Nexrad radar and cloud cover are animated and a finger tap leads to a choice of local forecasts, buoy data, and more, depending where you tap.  But finding a good place for this 18 ounce “portable” on your dash or at your helm may not be easy…

I don’t really understand why Garmin equipped the 640 with a 9 hour lithium-ion battery (it’s hard to picture pulling that 5.5″ screen out of a coat pocket), but I can tell you that the unit has enough mass to sometimes overcome the car mount seen above, despite its large, bendable, and sticky rubber base.  And you know it when this baby lands in your lap!  Now that same base will work fine at either of Gizmo’s helms, as would the marine swivel mount (below) that comes with the GPSMap 640 package.  I’m also pretty confident that the GXM40 Smart Antenna will bring in XM OK through the boat’s main cabin windows, but wonder where a sailor would mount it if he or she wanted to install the 640 on his or her wheel pedestal.  The antenna does come with a USB extension cable, and a choice of fixed or magnetic mounting plates, but will still be awkward at some helms. I also wonder if the the 640’s IPX7 waterproof rating — 30 minutes at 1 meter depth — still applies if the rubber USB port protector cap is open?
   Note that the marine mount’s power cable includes two NMEA 0183 ports (N2K would have been sweet, but these will work for AIS, wind, depth, etc.).  It also has stereo output wires, and both bases accommodate stereo mini jacks.  So you can use a 640 in many ways, including maximization of an XM subscription (now less expensive, but still not trivial).  I do wish the 640 showed more weather detail in street nav mode, but then again know that Garmin has pleased many customers by keeping things simple.  The marine nav mode looks good, except perhaps for its inability to do split windows, but I’ll save that discussion until I’ve really used it on the water.  I will note, though, that when Garmin says “modes” it’s not kidding.  The 640 (and probably its GPSMap 620 cousin) are truly dual boot devices.  It’s not a significant hassle, but the street and marine modes acquire GPS fixes separately, store weather data separately, and even get updated separately.