DeLorme Pn-60w, Digging Deeper
It is worth digging a little deeper into the technologies behind the new DeLorme PN-60w, and specifically the “w” (wireless) part. While some of the wireless features won’t be out until Fall, we’ll fuel some of the appetite now. We’ve seen many of the “front and center” features, now lets dig under the hood a bit more.
While the form factor stays the same, the chipset is sill 32 channels, and you still get a dual processor, not everything else is the same. You also get more memory, the wireless features, and the light sensor which automatically adjusts the display brightness. But other internal circuitry changes have been made as well, and the newly designed guts will help achieve better battery life. Battery life has been a sticking point with many DeLorme PN-40 owners.
Storage for Waypoints and Tracklogs
GPS devices are often compared against each other by how many points you can store in your tracklogs or how many waypoints you can store on the device. Hard-core geocachers for example love to store thousands upon thousands of geocache locations on their device. Hard limits are all but gone on the new PN-60. You can store as many waypoints and tracks as you can fit into either the internal memory or on SD card. When only limited by memory, you will soon be measuring the limit (if you want to call it that) in millions.
New Topo USA
There is also a new version of Topo USA that will come with the PN-60. While details are still a bit sketchy, it sounds like the infamous “Exchange Dialog” will be radically updated. Here, it is time to think more about “syncing” your PN device with a Topo USA project where you don’t need to worry about copying files in one direction or another and one button might sync up an entire project (tracks, waypoints, etc).
802 who? 802.15.4 also known as ZigBee…. Leaving the two most interesting features for last, 802.15.4 is the protocol used for wireless communications between devices. I wasn’t too familiar with this protocol, but it looks like a very interesting application well suited for GPS devices. You may be familiar with wifi protocols like 802.11b/g/n. Those protocols are often high speed, and thus high battery drain. 802.15.4 is a slower speed at 250 kbit/s, but the advantage is that it uses very little power. So there is little chance of doing any wireless syncing to your computer– keep your USB cable handy. But sending tiny packets of data between devices should be trivial and not kill your battery.
Another aspect of wireless and 802.15.4 is that it uses a mesh network. The DeLorme folks say that two devices can communicate pretty consistently when within a one half mile range, but that they’ve also had it working reasonably well up to one mile apart. But this is unlike the wireless router in your house where you need to be a certain distance from the central router to pass data. In a Mesh network, each device essentially becomes an access point for the rest of the devices. So imagine a long straight stretch of train tracks ten miles long. You have twenty people spaced about one half mile apart. In theory, the two people furthest away from each other, ten miles apart will be able to find each other on the network with their data having been relayed between each other.
It sounds like you will be able to determine who you make yourself visible to and remain stealthy from others. For those people familiar with the game “Capture the Flag”, can you imagine how fun it would be to have a massively large game in the woods where you can look down at your GPS and see the position of everyone on your team, yet remain invisible from the opposing team? That sounds like an amazingly good time to me!