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Geocaching FAQ

Note: This discussion reflects the use of firmware version 2.6 or better. Version 2.6 RTM became available on July 6, 2009. Geocaching features in version 2.5 are substantially similar. Earlier versions of the firmware do have support for geocaching, but it is not as complete as what we discuss here.

Can I use the PN-40 for geocaching?

Yes. The PN-40 fully supports paperless caching.

What do you mean by paperless caching?

You can download the full cache description, recent logs, hints, and other information directly to your PN-40. In the field, you can log your attempt (found, DNF, write note, needs maintenance). You can also write additional notes to track what you took or left, travel bug information, and so forth. Later, you can connect the PN-40 to your PC and upload your logs and field notes directly to geocaching.com. No more printing cache pages or penning notes in the field!

How do I get all that onto my PN-40?

As of 10/04/2009, there are a number of fully supported options.

You can send one cache at a time from the geocaching.com web site to the unit using Send to GPS. When you attempt this for the first time, you will be asked to download and install the free DeLorme Send to GPS plug-in. No other software is required. This feature works on both Windows PCs and Macs.
You can send Pocket Queries from geocaching.com to the unit using the Cache Register widget. Cache Register is a stand-alone DeLorme program. It is available for download at a cost of $10. This program works on both Windows PCs and Macs, although you must download a different version for each platform. Cache Register can download recently executed PQs directly from geocaching.com or it can use PQ results which you received via e-mail. Cache Register can also automatically synchronize your field notes with geocaching.com.
You can import a pocket query (or other .loc or .gpx file) into DeLorme Topo USA 8.0, then export the waypoints and caches it contains to the PN-40. Topo USA 8.0 is included at no extra cost will all new PN-40s. This program works only on Windows PCs. Note that Topo USA 7.0 support for geocaching is not fully compatible with version 2.5 and later firmware.
You can send multiple caches, including pocket queries, using GSAK. This requires a very recent (currently beta) version of GSAK (version 7.6.2.29 or better). GSAK is available via download. It is free to try (and free to use for as long as you can stand the nag screen on startup). A $25 contribution covers all updates to the current major version. This program works only on Windows PCs. **If you download the beta, please pay attention to the note. Be sure to download and install 7.6.1.27 or newer before installing the beta.**
You can send multiple caches, including pocket queries, using GPSBabel. In addition, you can use GPSBabel to upload waypoints, tracks and routes to your PC. This requires a very recent (currently beta) version of GPSBabel (version 1.3.7-beta20090906 or better). GPSBabel is available via download. It is free to try, with a requested $25 donation. This program works on WIndows PCs, Macs, Linux, and other platforms.

That's a lot of options. Which one should I use?

If your typical caching trip is pre-planned and you only do a few caches at a time, use the Send to GPS plug-in.

If you use pocket queries and typically load entire queries onto the unit, Cache Register may be a good choice for you. It does a very good job of managing unit content, even in situations where your pocket queries overlap (contain some caches in common).

If you are a "power cacher", GSAK is the obvious solution for you. GSAK gives you maximum control over just which caches you load at any given time. And you already use it anyhow, right?

Topo 8.0 USA also gives you the ability to mix caches from multiple PQs, then selectively load some subset onto the device. However, it tends to be cumbersome to use in this manner, especially when large numbers of caches are involved.

If you use a Mac, your only choices are Send to GPS, Cache Register and GPSBabel.

How many caches can I put on the PN-40?

Caches are waypoints. The unit will handle up to 1000 waypoints.

Is there any limit to the length of the data for a single cache?

Yes. The description, hints, and recent logs must not exceed 15,000 characters per cache (2,000 for the PN-20). Data over that limit is discarded.

I hate hints. Can I avoid seeing them?

Hints, if any, appear after the description and the logs. You usually have to page down quite a ways to see them.

I need hints. Is there a quick way to get there?

Yes. From the top of the description, tap the up arrow on the rocker. This takes you directly to the end, where the hints are hiding. Starting with firmware version 2.6, you can also use the View Geocache Hint option which is available on the menu on the Geocache Detail Page.

I only like regular/multi/puzzle caches. Can I see the cache type?

Yes. The PN-40 uses the same cache icons as geocaching.com. Once you have logged your attempt, the cache icon changes to reflect the type of log (found, DNF, note, needs maintenance). These icons appear both in the cache list and on the map.

Why does the pointer jump around when I get near the cache?

You probably have the electronic compass enabled. First, be sure the compass is correctly calibrated. If so, the problem may be due to multi-path problems in challenging reception conditions. In this situation, the unit may be unpredictably switching back and forth between the direction of travel indicated by the compass and false direction information provided by multi-path satellite data. In this situation, it may be best to disable the compass temporarily. It may also be jumping around because you're still routing to the cache using "Drive" rather than "Hike" navigation.