Earthmate PN-40 GPS by DeLorme – Geocaching, anyone?


Most people hear GPS and the first thing they think of is dash-mounted vehicle units to help guide you in the car.  I’m here to talk with you about GPS when your method of travel is by bike, foot and car.  The DeLorme Earthmate series handheld GPS are perfect for hiking, biking, boating and more, but what I’m really raving about is the world of possibilities a rugged and handheld GPS unit opens up for a family on the go.

By far the coolest thing about the PN-40 was that it introduced us to geocaching, and now has become our newest obsession.  For those of you who are not familiar with geocaching, it is my pleasure to acquaint you with the coolest pastime ever.  Geocachers all over the world hide little treasures and notes in just about any place there’s human access and then leave the GPS coordinates of their cache on sites like http://www.geocaching.comUnlike most hobbies that require large amounts of your disposable income, geocaching is free and the only equipment necessary is a handheld GPS unit like the DeLorme PN-40.

As well as being fairly inexpensive once you make the initial GPS investment, geocaching is quite addictive and has led us to do some crazy things.  Like hunting for treasure in the middle of the night with only flashlights to guide us, hence our geocaching alias, the Night Cachers.  My favorite caches are those with clues or hints that make you feel like a super sleuth when you finally find your treasure and makes the reward that much sweeter.  It’s a great activity for kids of all ages and adding to the fun of finding buried treasure is that a lot of caches are designed for you to swap items or add to the original cache, so your toy or knickknack is added to the booty for the next cachers to find.  It’s a great way to insist your little ones purge their collection of tiny toys that were so cool – but then only played with for a few minutes.   


What makes the PN-40 so great for geocaching are the maps that DeLorme makes available to you.  For $29 a year you have unlimited access to their database of maps in formats other GPS makers can’t even dream of, including NOAA marine charts, satellite imagery, high resolution aerial photos in black and white or color, and scanned USGS topo maps in 1:24,000 scale.  And best of all, you can layer the different types over one another just by clicking a box in the menu screen.  So if you are having trouble finding a particularly well hidden cache, you can just open up the aerial imagery you previously downloaded to your PN-40 and see a birds eye view of where you are, which is much easier than deciphering topo lines or the streets and blank spaces of typical GPS units. 


This feature can also help you learn how to read traditional maps better by combining a satellite image with a topographic map you can really see how the lines follow the contours of the land and get a much more full view of every hill and valley, and then in the future have a much clearer image of how maps translate to reality.  This makes it the perfect way to get kids interested and to help them learn to navigate on their own.  The new PN-40 also features a barometric altimeter and a built in compass that does not require you to hold the unit completely flat for it to work correctly.  These, in conjunction with the maps, make it virtually impossible to get lost.  Even when you’re trying to.

If you feel you don’t need all the extra maps, fear not, the PN-40 comes with DeLorme’s own Topo USA map software including streets, trails, and points of interest for all 50 states.  The software is a little technical but with some practice will let you do amazing things and allow you to fully utilize your GPS.  Let’s say you want to go hiking; you can plan your trip all the way down to which roads you want to take and what kind of elevation changes you will be going through.  Then when you return you can see where you went and even show it off by tagging your pictures to specific coordinates to share with others online. 

The actual PN-40 is extremely durable, which has been tested more than once in our many travels with it and children.  In fact, baby pretty much thinks the Earthmate GPS is just about the coolest toy she’s ever seen and finds it very convenient that it hangs right where she rides in the front pack.  In the months we have been traveling with the PN-40, the unit shows little sign of wear and tear and still performs as good as new.

The unit is similar in size to a remote control and has large, rubberized buttons that are easy to navigate and press while gloved or while cycling.  The battery compartment is water tight and secure, designed for extreme conditions and tough travels, which means that it is kid safe – or mama safe, as the case may be.  The battery life was slightly disappointing in the rare instance when the satellites were having a hard time getting their fix and the PN-40 was searching for our location for long periods of time, but the battery life seemed fine under normal circumstances.


The screen itself is a little smaller than some other GPS units out there, but produces a very clear and sharp image, which combined with the rich map content more than makes up for it. In direct sunlight, or in the middle of the night it was always easily readable.  In addition, the super-fast processor means that as you move around, the PN-40 has no problem keeping the map up with you even while traveling by bike or car.

Speaking of bike rides, after our first bike ride with the PN-40, it’s hard to imagine going without it.  With the use of its proprietary mount it easily attaches to your handle bars in minutes, and from then on snaps in and out in seconds.  The tracking features really come in handy as you can at a glance see your current, average and max speed, your total trip time as well as time moving and stopped and total distance traveled.  Then you can switch to the map screen and see exactly where you’ve gone or where you need to go.  These features while great for hiking, proved awesome for biking as it made us really push ourselves, and also kept the kids interested in the ride much longer as they questioned our latest stats.  And they especially liked being able to search for the nearest frozen yogurt shop in the middle of the ride. 

Ways to make it even more Ravetastic: 1) My husband’s sick of me saying this, but the lanyard really should attach to the bottom of the GPS unit.  Sure, that means it hangs upside down on your neck, but who cares?  Then, when you go to pick it up or check the maps quickly the unit would be right side up.  Makes sense, right? …right?   2) While it’s a powerful workhorse off road, navigating by PN-40 in the car is a little trickier in that there are no voice prompts.  Instead of a voice saying “turn right here”, the unit merely chimes.  Some people might prefer this, but some might do better to have a passenger seat navigator with the Earthmate PN-40 controls. 

Key Features of the DeLorme PN-40 Include:

  • 32-channel STMicroelectronics Cartesio chipset
  • 3-axis electronic compass
  • 500 MB of available onboard Flash memory
  • Support for high-capacity SD cards (SDHC) up to 32 GB
  • Dual-core processor for blazing-fast performance
  • Barometric altimeter
  • Fast USB 2.0 data transfers to in-device SD card – no external card reader required
  • More detailed onboard base map data for the U.S., now with secondary and connector roads, along with major highways and thoroughfares for the entire world (still providing detailed U.S. street and backroad detail via the included Topo USA software).
  • Price: $270 – $399, with many sites offering free shipping and also available as a geocaching bundle.  Bicycle mount mentioned in review runs $25 at most sites.

    Overall:  A lightweight but rugged handheld GPS with beautiful maps and serious tools for casual and seasoned outdoorsman alike. 

    Stay tuned for our complete run-down of geocaching with the kiddos with the Earthmate PN-40.  We will be geocaching throughtout NYC and Seattle, as well as taking to the mountain and trailside to show you the abundance of geocaching options that are right outside your door.

    4 thoughts on “Earthmate PN-40 GPS by DeLorme – Geocaching, anyone?”

    1. The accuracy in great but I was so excited to get this machine because of the recharging ability. It only lasts about 30 minutes which is not much good to geo-cachers. Also, if you are a Mac user there is not any software available. DeLorme puts out something called Cache-register but I installed it on several Macs and it crashed on all of them. It does not work. Tech support – not available.


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