parkrrrr

But they won't help you know where you are inside your house or under heavy tree cover. They work exactly as I described, and they are only useful because their receiving antennas are rarely very far from your GPS receiver.

Just the laws of physics. GPS works by measuring the time delay between your receiver and the transmitter on the satellite. With four such measurements, a little math, and a knowledge of where every satellite is in space at any given time, you can compute your location in space. A repeater would have the effect of making your receiver think it was always at the location of the repeater's own antenna, and of making your system clock be off by a tiny fraction of a second.

http://watcher.clayjar.com If that's down, it may be you. It seems to be working for me, from two different computers on two different ISPs.

See, therein lies the problem. There aren't two choices. There are at least three choices, and possibly four if you see GPX2HTML/Plucker as distinct from Spinner/Plucker (I do.) People who pretend that those two programs are the only two that exist are doing everyone a disservice.

I didn't like any of the available mounting options for my Meridian Platinum, so I created my own mount with a length of copper tubing and the backplate from the Magellan swivel mount. The power cord plugs into one of the three extra power points I added under the dashboard. Unlike the two stock power points, the extra ones turn off when I turn off the key (because I also use them to power some higher-drain devices like a thermoelectric cooler, and I like for the truck to start in the morning.) The only thing that doesn't work at this angle is the magnetic heading, because the unit isn't pointed in the same direction the truck is going. The rest of my caching stuff fits in and on a small shoulder bag, which I keep behind the driver's seat.

Every time this topic comes up, it seems like it polarizes into a CacheMate Vs. Spinner/Plucker rumble. Why is it that we take up arms for the cause of a simple bit of software, just because it works for us? Is it a need to feel validated by being in a large group? Do you CacheMate users have trouble sleeping knowing that People Out There Are Spinning And Plucking Right This Very Second? Different people have different needs and different skill levels. Instead of arguing about how easy/quick/mindless your particular program is, why not just tell us what it does and how well it works for you and let us decide? That said, here are some other programs that might be of use if you're using a Palm to geocache: Watcher - easy to moderate skill level, Windows only. Use Watcher to organize, filter, merge, and sort your cache descriptions before uploading them to your Palm. GPSBabel - moderate to difficult skill level, cross-platform. Use GPSBabel to filter your GPX files before further processing, or to convert them into formats usable with various Palm software (even if you have a standalone GPS, programs like GPilotS and GeoNiche might still find a place in your caching portfolio.) GPSBabel is Free Software/Open Source, in case that's important to you. GPX2HTML - moderate skill level, cross-platform. GPX2HTML does mostly the same things Spinner does, but depending on your particular skillset and available tools, you might find that you like it better. GPX2HTML is Free Software/Open Source, in case that's important to you. GPXDoc - easy to moderate skill level, Windows only. GPXDoc converts cache descriptions into PalmDoc format. If you already use a PalmDoc reader for other things, or if you use an older Palm with limited memory, give GPXDoc a try. In my opinion, which is undoubtedly biased since I wrote the program, the nicest feature of GPXDoc (when used with CSpotRun, TealDoc, or similar reader on the Palm) is the ability to choose your cache from a dropdown list and jump right to it, without having to use your program's "search" function or go back to the table of contents. What do I use? GPSBabel and GPXDoc. But that's because that's what works for me. Try them all and use what works for you.

My copyright notice - not a disclaimer - reads as follows: As you see, it does not conflict with the geocaching.com terms of use. What it does do is: establish the name of the original creator of the data remind the person who plans to use the data unscrupulously that it's not just geocaching.com they're screwing over give me slightly more leverage if I wanted to press copyright violation claims myself, should geocaching.com decline to do so for whatever reason (provided they did so without giving the third party an explicit license to use the data; if they did, the use would fall under the TOS.) document the copyright for materials that don't fall under the TOS, including any images or other files that are linked from my personal webpage. Of course, I'm not a lawyer. I'm not even related to any lawyers, thank God. Maybe this stuff wouldn't stand up in court. But it's probably better than nothing.

It does. I just checked a PQ that contains one of my own caches, which have the same sort of statement.

Not yet, though there used to be a multicache in this neighborhood that led people along similar trails in a more scenic area. (That trail, or sidewalk, or whatever you want to call it, leads between the two drainage ponds and to another street. Not a lot of cache-hiding opportunities there.)

Fine by me. That's my neighbor's lawn.

AOL uses Internet Explorer internally, so the answer is a definite "maybe." I'm guessing not, though.

Not these, no. The US in USGS stands for, well, "US."

Nah. I just started paying someone to mow for me. More time for geocaching.

The house on the southwest corner of that T intersection there is mine. Notice how much greener it is inside the fence than outside? Did I mention that I have dogs? Other things you can see in this picture that surprised me: The oil spot in the driveway where I used to park my '88 Tempo, which leaked a little. The shadow of my trash can (this picture must have been taken on a Wednesday.) The shadow of the street sign on the corner (which is approximately a 6x6 wooden post.)

Just to be clear, these are not satellite photos. These are digitally orthorectified aerial photos, taken from airplanes. I suspect the choice of cities that's available reflects the cities that have their own aerial photography programs in place; I know that Fort Wayne and Allen County were working on a comprehensive county-wide GIS as long as 10 years ago, for example, so the cost of acquisition was minimal for USGS. That would explain, too, why there are licensing issues with some of the California data.

While I was poking around on the USGS site looking for elevation data in a usable format, I came across the "Seamless National Map Viewer" application. And while I was poking around in that, I found something that may be of use to some of y'all: really high resolution (1 pixel = 1 foot) aerial photos of select metropolitan areas. You can also overlay a lot of other useful data layers, including roads and water features. Their news page currently contains a list of the metro areas for which imagery is available. I downloaded the GEOTIFF version of this imagery for about a square mile around my house and enhanced the color a little. (I don't recommend doing so; I ended up downloading about 240 megabytes of uncompressed imagery for just that small area. Dialup users beware.) This is what a piece of my neighborhood looks like on Terraserver: And this is what the same area looks like with this new data product (with the color enhanced a bit - I cranked up the saturation by 50%):

While poking around on the USGS site, I came across http://seamless.usgs.gov , which allows you to either download or purchase various kinds of geospatial data. Included in that data are the recent SRTM elevation maps, with a resolution of one arcsecond (about 30m north-south, east-west depends on your latitude.) If the area you're plotting isn't too large, you can even download the data for free. The data itself is available in various formats, but GEOTIFF is probably the most useful of the bunch. If you search around on the Internet, you can find various utilities to deal with GEOTIFF files, but gluing them all together to extract a single point might be more difficult. However, if you have the budget to hire a programmer for a few hours, or if you're a programmer yourself, that might be the most cost-effective solution.

See here for what documentation there is on the subject.

Yes, but it might be able to tell your *computer* something it didn't already know. For example, I have a database of my DVD collection that was built by using Amazon's .NET service and a barcode reader. Sure, I know that I'm holding Season 3 of The Simpsons, but why type that into the computer if I can just scan the UPC on the back?

Yuck. For that, you'll probably need a good GIS application, and lots of data from USGS or some other agency. The data is free. The software, however, is generally not. You might want to go to the USGS site and see if someone's written software to do what you need using DEM (Digital Elevation Model) files. I think they used to have links to software, but maybe they don't anymore.

Not unless Mozilla understands IE "Explorer Bars." In other words, probably not. It's really just a painfully simple little web page, combined with some registry magic to make IE see it as "special." I'm pretty sure Mozilla has something similar, but I haven't used it enough to know what you'd have to do to make it work.

Go there and look at your GPS? How many points are we talking about here? I don't know that you'll be able to find a reasonably-priced program to do it in bulk, so you may end up doing it by hand. Personally, for a handful of points, I'd just pull up the topos on terraserver and see what I could see.

It has come to my attention that the URL used by my geocaching.com search toolbar points to my web server by its numeric IP address. Normally, that wouldn't be a problem. Sadly, my ISP has decided that dialup is the future and are dropping all broadband customers at the end of the month (And no doubt going out of business in March, but that's just my opinion.) That means my website will likely be moving soon, and all of you who have been using my Geocaching.com toolbar will find yourselves staring at a "server not found" message instead of a toolbar. Fortunately, there's an easy way to fix this: If you're using the toolbar, please re-download it and re-install it so the URL can be corrected to one that shouldn't cause this kind of problems. Sorry for the inconvenience.

The neat thing about UPC is that it looks the same backwards and forwards, the only difference being that the combinations of modules you get when you scan it backwards don't correspond to any digits. The reason is that the dark-light-dark "start" code calibrates the scanner so it can compute how much color bleed there is due to the printing process, what the ratio in reflectivity between the dark and light bars is, and what the basic width of a module is. Since the scanner can encounter the code in any conceivable orientation, having it start the same way it ends makes the calibration process that much easier. Upon examining a few film envelopes, I'm led to believe that the 2-of-5 and Interleaved 2-of-5 codes also have only two possible widths of bars, ruling them out as well. I'd venture a guess that the most likely explanation of the bars on the travel bug tag is that the person tasked with creating it drew some random pixels that "looked like" a barcode. This is easy to do with the Photoshop noise, threshold, and motion blur tools (followed by a little antialiasing, for some reason I fail to comprehend. Perhaps it was scaled down after production.)

With a little work in Photoshop, I've extrapolated from the image on the "track travel bugs" page to this: However, this is not a standard UPC code (so the suggestion that it scans as "peaches" is unlikely.) Every UPC code has features in common: each code starts with a dark bar of width 1, a light bar of width 1, and a dark bar of width 1. Every digit in a UPC code is the same width, 4 bars (dark and light) with a total width of 7 "modules." On the left side of the separator, each digit consists of a sequence of light-dark-light-dark. The center of the code is indicated with a 5-module sequence of light-dark-light-dark-light. On the right side, digits are the inverse of their representation on the left side: still 7 modules, but starting with a dark bar. Finally, the whole sequence ends with another 3-module dark-light-dark sequence. Your garden-variety grocery store UPC barcode begins with a 0 and is 12 total digits (The first digit is the type of product, the next 5 digits are the manufacturer's ID, the next 5 digits are the product ID assigned by the manufacturer, and the last digit is a checksum of the first 11 digits.) If you attempt to interpret this barcode as a UPC code, the first thing you see is that it doesn't end (or begin, depending on which way you look at it) with the required 3-module dark-light-dark sequence. The second thing you see is that it consists of at least 18 pairs of dark bars, whereas a grocery-store barcode always consists of 15 pairs (one pair for each of 12 digits, plus one pair each for the start, middle, and end.) Also, you discover that the groups of bars are not the same widths, which is impossible in UPC. So it's not likely to be a product that your local grocery-store scanner will recognize. The observation that the groups are not the same width also torpedoes Code 39, which is a common alphanumeric code (The fact that there are more than 2 widths of bars also works against Code 39.) It might be a 2-of-5 code, which is what is used on the envelopes you get when you take film in for processing, but I don't have any experience with 2-of-5 so I couldn't speak intelligently about that. If any of you have a barcode reader, feel free to print this and scan it and see what happens. I'll try that myself next time I find my Cue:Cat.