Delorme Earthmate PN-30 GPS Review

I most always carry a GPS receiver when I am on photography trips. Aside from being invaluable for storing points of interest or great photography spots, they work much better than a pedometer in tracking how many miles you've walked.

Attracted by its interface with the DeLorme Topo USA mapping software and its ability to display not only DeLorme topo maps but also to overlay aerial imagery and USGS topo quads in its display, I purchased the Delorme Earthmate PN-20 GPS receiver shortly after it was released in 2007. In all, I've been very pleased with the PN-20, but it's not without it's quirks:

• Its flexibility in loading topo maps into the unit is unparalleled, but the process of "cutting" maps in the Topo USA software and uploading them to the PN-20 is cumbersome;
• From a cold start, it seemed to take a long time to really figure out where it was. Often I would turn on the unit at the trailhead, wait until it had determined it's position, waypoint the trailhead location, and start hiking. Yet when I returned to the trailhead (that I had waypointed when I left), the location it displayed upon my return was often many tens of feet away from the original waypoint (even though I was standing in the same spot);
• The overall responsiveness in paging from one screen to the next, rendering maps and screen refreshes is sluggish.

DeLorme announced the PN-40 GPS, the next-generation of the PN family of GPS receivers, in early 2009. Its documentation and reviews indicated that it addressed all of the complaints that I had about the PN-20, but I hesitated buying one, not wanting to lighten my wallet by another $400 (although DeLorme has offered it for sale a number of times since its release). Then the PN-30 was announced in July: Same performance as the PN-40, without the electronic compass and barometric altimeter, for $100 less. Be still, my beating heart. When REI put it on sale for $200 during their Labor Day sale, I beat a direct path to the store on the first morning of the sale and purchased one. The electronic compass and barometric altimeter just weren't worth the extra $100 for my purposes.
The DeLorme PN-30

The PN-30 looks virtually identical to the PN-20 and PN-40, except it is available in green (the color I chose, see photo) and in camouflage. But it features a number of improvements over the PN-20:

• 500MB of internal memory (versus 75MB for the PN-20);
• A dual-core processor for better responsiveness and faster screen redraws;
• A 32-channel GPS chipset (versus a 12-channel chipset in the PN-20);
  
  
• Topo USA version 8 (the current version of the PN-20 ships with version 8, but mine came with version 6, and I hadn't upgraded;
  
  
• DVDs with precut maps of the entire US, broken up into regions. This eliminates the need to cut and process maps from Topo USA, just choose the region you want from the maps DVD and upload it to the PN-30.

First Impressions

On first startup, even indoors, the PN-30 acquired satellites and had a position within a couple of minutes - impressive for a cold start from factory defaults. A quick trip to the computer to upload the precut map for North-central Colorado, and I was in business.

A hike up Hewlett Gulch the next morning confirmed that the PN-30 is everything I had hoped it would be. Turning on the PN-30 at the trailhead, it acquired satellites and had a position in under a minute. A quick waypointing of the trailhead location, and we were off. I was immediately impressed by the PN-30's responsiveness compared to the PN-20. Zooming in and out on the map, the screen redraws were almost instantaneous, as was switching from one screen to the next. Returning on the same trail, the "breadcrumb trail" path drawn on the GPS screen for the "return" leg of the hike was perfectly superimposed on the path from the "out" leg. Upon returning to the car and standing on the same spot that I waypointed when I left, there was virtually no difference between the "before" and "after" positions. So the minor positioning errors I used to see with the PN-20 appear to be fully resolved with the PN-30.

I haven't had an opportunity to download and install supplemental USGS quads or aerial imagery from the DeLorme map library, nor have I played with the Geocaches page, and the ability to download geocache information from http://www.geocaching.com/ - I hope to play with those features and provide a follow-up report soon.

Conclusions

DeLorme has done a great job in addressing the shortcomings that I had found with the PN-20. With the precut maps included with the PN-30 (included in the price), Topo USA Version 8 software for more ambitious mapping projects, and the improved responsiveness and accuracy of the PN-30, I can't think of much more that I would want in a GPS. I haven't compared the PN-30 to competing GPS models from the other manufacturers, and I would encourage you to do so if you are making a purchase decision for a GPS. But for me, the upgrade to the PN-30 from the PN-20 has proven to be an excellent decision. I think the PN-30, with its accompanying maps and software, is a GPS that I can live with for many years to come.