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One Chicken to Rule Them All

My wife told me earlier today that she thinks I like to write. After all these years of marriage, I was shocked that she didn’t understand me at all.

I hate to write.

I’ve hated writing all my life and yet here I am, writing again.

For the most part, I write what I write because if I don’t, it won’t get said – or, at least, it won’t get said in the right way.

If you look at my writing with that thought in your mind, you’ll see why so much of my writing is (I’m told) somewhat acerbic. There are things that need to be ridiculed, at every opportunity, like Creationists, because they get too much credibility or too much deference when they should be laughed out of the room.

Chinese nationalism is like that, too. Check out this blog post from Laowisewass*, which, I kid you not, points out that a good reason to “unify” Taiwan is so that China won’t look like a legless chicken on the map. Admit it, you sit around laughing at China, the legless chicken, at least once a day, right?

(If there’s a comment there about Col. Sanders, that was me.)

This idea makes complete sense to me. I know that’s the first thing I do when I look at a map, I try to make pictures of animals out of the countries. Is it any wonder that the island of New Guinea is such a mess? I mean, obviously, it’s a kangaroo, and Papua New Guinea is its ass. Their destiny was sealed by geology!

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*It’s not often that I’ll wax enthusiastic about someone’s internet screen name, but “Laowiseass” is a fantastic name. “Lao Wai” (Pronounced: “lao why”) is a somewhat uncomplimentary name for a foreigner. Laowiseass, is just hilarious.

Technorati Tags: Chinese, Commentary, Taiwan

2008-01-20

My GPS – Garmin Vista HCx – Review

This article of a three-part series. Part One detailed my history with GPS units over the last 12 years.

This part picks up with my selection criteria and impressions of the Garmin Vista HCx GPS.

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Being a computer-oriented person, my first “requirement” in a GPS was convenient data access to a computer. That was true years ago when the process was rudimentary, and it is even more true in this age of Google Earth and travel routing GPS systems.

My list of requirements:

After much research, I zeroed in on the Garmin eTrex Vista HCx model. Garmin makes several lines of GPS, but I opted to stay with the eTrex models based on familiarity and, among the different lines, the available options are generally the same, with a few exceptions. Within the eTrex line there is a plethora of models these days, ranging down to the basic model that my dad has to the high-end Vista HCx.

Since I got it, three weeks ago, I’ve also purchased a number of “accessories”, including mounting hardware, data card, maps, etc. I’ll try to address them in the next article.

Accuracy

It would be hard to argue otherwise that a GPS’s utility lives and dies by its accuracy. So far, this unit’s accuracy has been exemplary. We can try to shoehorn in Heisenberg’s Principal of Uncertainty and argue in a somewhat roundabout way that I can’t be certain about the accuracy because I’ve can’t be certain of the accuracy of the original measurement of the point I’m trying to compare measurement to.

In short, how do I know for sure that the GPS is leading me to the actual spot I told it to?

The best I can do is try to assess how I’ll use the GPS, and go from there. How will I use the GPS? Largely with Google Earth, so the accuracy has to tally with Google Earth.

I’ve taken several clearly identifiable points in the Google Earth satellite imagery, such as the basketball goal in my father’s backyard and marked the waypoints. I’ve transferred that waypoint to the GPS and navigated to the waypoint. Under those conditions, the accuracy has been consistently approximately 10 feet. (Garmin literature indicates 9′ accuracy with error-correction turned on. My tests indicate there’s no reason to dispute that.)

My second series of tests involved going to areas with a visible landmark, such as an isolated tree in a park, and snapping a waypoint using the GPS. I then transferred that waypoint into Google Earth and compared the placement with the actual landmark. Again, the point is almost always off by approximately 10′.

Note, I said “off” by 10′, not “within” 10′. In every test, the waypoint has missed the landmark by 8-10′ as measured by Google Earth’s measuring tool.

The third way I tested it was to snap a waypoint at a known landmark, then, on another day, attempt to return to it.

I wasn’t sure what to expect with this test. Would the inherent error is the taking and the reading of the measurements cause the error to compound each other? Cancel each other out? or both? Answer: Both. The error factor was a lot more variable, and stretched, on one occasion, to nearly 20 feet. Generally the error was in the 5-15′ range.

That indicates to me that the error factor of a GPS has to do with time-dependent factors, rather than the algorithms used to compute location. If it were the algorithms, I would except finding this particular type of waypoint would be the most accurate, since the algorithm would “re-create” the same error at the same location.

Summary of accuracy: I’m completely satisfied that the unit consistently works to the manufacturers specifications.

Reception

So far, I’ve had extremely fast acquisition of satellites, outdoors and in. The only exception is at my office, which the 4-storey metal-framed building blocks practically ever kind of signal.

Operation & Controls

The eTrex Vista models evolved from the earlier eTrex model, which is what my father owns. The eTrex was originally designed for left-handed operation. The literature said that this was so that your right hand was free for carrying walking sticks or whatever. We’re both right-handers, and almost never use the eTrex in the left hand.

The Vista, on the other hand, although I didn’t notice any explicit mention of it in the manual (such as it was) follows the left-handed convention, although the buttons are different from the eTrex because of the more complicated menuing system. The unit can still be operated in the right hand, but the additional thumb control on the front is clearly positioned for the left-hand thumb. Access from the right hand requires your thumb to cross the screen, or shifting the GPS to an awkward position.

This has been giving me a little trouble since I’m used to holding the eTrex in my right hand and prefer it that way under most conditions.

Apart from the thumb control on on the front, the other controls are on the side of the unit, keeping your fingers away from the screen.

The top two controls on the left work the zoom, up and down. Below them is a “menu” button, which serves roughly three functions. First, press it once on any screen, and the menu for that screen pops up. Press the button twice (or press it again when in a screen menu) and the system main menu screen is brought up, which may save you a long trip through the screens. Finally, press and hold the button, and you are taken directly to the “find” screen.

On the right side, the top button is the “page” button, and also the cancel that dismisses menus or other dialogs. This button, when held in for a while also turns on and off the electronic compass.

The lower button on the right is the power button and also the button for activating the backlight.

On the front is the thumb control, which navigated through menus and when pressed, is the “Enter” key. I have the most problems with the thumb control. It navigates fine, but the Enter press has to be straight down. If you press at any angle, it seems to cancel what you’re doing. Big, clumsy thumbs need not apply.

Menus/screens

The eTrex Vista HCx is operated via a series of screens, such as the main menu, the compass, the map screen, etc. You cycle through them using the page button. The screens that you see, and the order they appear in are configurable. If you have too many screens, it can become a chore to “cycle around” to the screens you normally use. From the main menu, you can choose to go directly to any screen that you don’t have in rotation. If you do have that screen configured to be in the rotation of pages, it doesn’t appear on the main menu anymore. I think this is a flaw.

When you manually select a screen from the menu, if you then hit the page key to see another commonly-used screen, you can’t get back to the first screen without going back to the main menu and selecting it from there again. I haven’t (yet) come to the right customization of screens so that I don’t feel inconvenienced from time to time. Still, it does have a lot of available screens, many of which I never care to see, such as the one for timing a high-altitude parachute jump.

Briefly, I’ll touch on several of the screens that I use most commonly.

The Main Menu – Always available. Lists all the functions you don’t have configured to be screens. Setup and Find are also on this menu.

Compass – The compass is, not too surprisingly, a graphic representation of a compass. The compass heading is derived principally from the navigation data as you move. When you stop, GPS compasses become confused. the Vista HCx model includes and electronic compass for use in these times. Because it drains power, the compass doesn’t activate until you’ve been motionless for a certain period of time. You can also deactivate it completely if you don’t want to come on when you stop moving. If you’re navigating to a point, the compass also has a pointer to show which way you should be going.

There are also some data displayed on the compass screen, which I’ll get to when I discuss the Trip Computer

Trip Computer – The Trip Computer is basically the “Geek screen.” It’s a data read-out display of 8 different facets of your navigation. You get to choose which ones from a long list. Some examples of the types of data: elevation, speed, course, odometer, distance to next destination, distance to final destination, current ETA as destination, and a whole raft of others. These fields are configurable, and you can also switch to a “big numbers” mode for people with difficulty reading the small screen. You only get three data fields in big numbers mode.

The ability to pick and choose you data displays is also available on other screens, such as the Compass, the Highway display and the Map. On those screens, you have fewer available data fields, but you have the same selection pool to choose from. I like this customization, and I’m still experimenting with the “best mix.” I tend to like different information depending on how I’m navigating and, like the choice of screens, I haven’t quite found what works best for me yet.
Map – The map represents a top-down view of where you are, relative to other waypoints and map points in the system. It also shows a breadcrumb trail of where you’ve been, and a course line to where you’re going.

Out of the box, the Vista HCx only has a North American base map which includes major highways and interstates, plus some rough waypoints for locating major cities. This unit is compatible with Garmin’s MapSource products, but in the interest of keeping this review a bit shorter, I’ll save reviewing the GPS w/maps for a later post.

Extra Features

The various lines of Garmin GPSes have a variety of different “levels”, for example, the “H” in HCx is for High-Sensitivity, which means it is a WAAS-enabled unit. (WAAS is a air navigation aid designed to augment GPS accuracy), The “C” is for Color screen, and the “x” designates that the unit accepts MicroSD data cards.

The eTrex line, in addition to the basic and the Vista models, also includes the Summit, the Legend and the Venture. It’s not important to differentiate them here, but the features that differentiate the Vista models are the electronic compass and the barometric altimeter. Without those features, the eTrex Legend is virtually identical, with a list cost of over $50 less.

Both the altimeter and the compass work, but need calibration, particularly the altimeter which is subject to changes in air pressure associated with storm fronts. GPS-calculated altitudes are notoriously inaccurate, and if you want accurate altitude info, the extra cost for the altimeter may be justified. However, if you load topographical maps into the GPS, the waypoint marking process will use the more accurate data from the MAP to set the altitude. (Or so I’m told.) This might be an alternative for some people rather than the altimeter option.

Data Interface
Unlike many older Garmin units (and even some current ones), the Vista models use a USB interface, rather than a proprietary serial cable. Not only does that make it easier to connect to modern computers, but USB supplies power to the GPS, conserving battery life.

To get the data to and from your computer, you need software, and since I’m exclusively a Mac user, that can present problems since it’s still standard practice for device manufacturers to concentrate on Windows users first, if not exclusively.

Garmin is at least working on OSX compatibility, and they provide several downloadable OSX-based utilities, such as a firmware updater and map and Point of Interest loaders. Also, there’s a web-based waypoint loader, used at places like geocaching.com or motionbased.com that allow you to interact with web sites and up and download waypoints. I’ve used both the firmware updater and the online transfer utilities and both worked flawlessly.

What I really need is import and export from Google Earth. For $20 you can upgrade to Google Earth Plus, which lets you connect your GPS to Google Earth, for importing and real-time tracking of your position, but it doesn’t support plotting waypoints in Google Earth and sending them to your GPS. That makes it next to worthless for planning any kind of excursion.

What I found was a program called GPSBabel+ which not only converts to and from most GPS-like formats, but can import/export directly to/from the Garmin GPS.

With these free resources, the Vista HCx works well with a Mac, save for using maps, which is awkward and requires some expensive “extra” software. Which I’ll describe in the MapSource post.

Misc

When my dad got his first Garmin GPS, it included a big manual, and even a video on using the GPS. When he got his eTrex, it at least included a helpful manual. The manual for the Vista HCx really assumes you already know all you need to know about GPSes, and does a poor job of explaining the functions. The Garmin website FAQs and such are also nearly useless.

I hope this isn’t intentional to drive sales of training videos or books. They really need to improve their documentation.

The color screen is a bit difficult to read in daylight, and I find myself turning on the backlight even during the day, which ought to be unnecessary.

Conclusion

The Vista HCx is an impressive all-around, hand-held GPS.

“Garmin eTrex Vista HCx Color High-Sensitivity Mapping Handheld GPS” (Garmin)

Technorati Tags: GPS, Review, Technology