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Mapbast gives you the lat/lon of any address you give in the corner of the map. It even will make your directions into GPS routes with a little tweaking. Combine with a $90 eTrex for a cheap OnStar system.

Besides, it's line-drive directions are the coolest.

I used GPSdrive for a long time, very good program.

As far as which GPS to use: any of them. All GPS's that I know of use the same standard to transmit data to a PC. It's called NMEA. Garmin makes a good GPS, it is what I used with GPSdrive. For a real good product, they are in the middle of the price curve.

If you are handy with electronics, you can make your own data link cable, there are instructons on the net.

eCycling is my Specialized Ground Control Comp A1 equiped with hokey spokes, Garmin GPS, Bike Brain and a 1,000 song sound system.

I use GMT and USGS data to make topo maps for my GPS. I get the data from my Garmin eTrex Venture with GPSMan.

It's all free, but takes some work. See my page of details and examples.

Look into NTP. Its low level protocol is not about setting the time but finding out how far wrong the local clock is by using other clocks that aren't quite right either. Most versions of NTP know how to speed up or slow down the local clock to help bring it into the correct time. This only works for machines that are always on and in a enviroment with a stable temperature. Other time protocols are based on the concept that one clock is always right and there is a cascade of error.

All current versions of cisco IOS do NTP. If you have serveral routers, tell them all to do NTP. I tell all my boxes that their ntp server is their default router to make life easy. The problem is they will need a time source and you said you can't connect the net. If you have a big cisco router, you may be able to hook a GPS clock up to it. You could hook up another server that gets its time from GPS or WWV or dialing into the US navy or temporary connection to the net and using ntpdate. The routers will help smooth out the time jumps and the other server will keep the time within a second.

The serial NMEA sequences out of most GPS recivers are not very good and tend to cause NTP to drift. Motorola used to make a GPS reciver just for time but they no longer make it. If your looking at just using any GPS, the $160 Garmin GPS 17 can be mounted on a pole outside and has RS-232 out. If your more into raw electronic modules, their GPS 25 has a 1hz signal out.

I've got two solaris servers at work that I use ntpdate to force a time update using cron. One drifts 2 seconds a day and the other .5 seconds a day. A typical pc will drift about two minutes in a month.

Remember lighting likes antennas. GPS antennas tend to work better in out of the way places than WWV antennas. A GPS antenna will work with just a 45 degree cone view of the sky.

I have a Garmin eMap. The flash upgrade feature is great, I probably would've had to buy a whole new unit to get the kind of features they've packed into the latest firmware update.

The list of corrections and features they've added to this thing is amazing. The eMap was useful before, now it's downright a necessity when I'm traveling.

I have a Garmin eMap. The flash upgrade feature is great, I probably would've had to buy a whole new unit to get the kind of features they've packed into the latest firmware update.

The list of corrections and features they've added to this thing is amazing. The eMap was useful before, now it's downright a necessity when I'm traveling.

They've had this for a long time in hand-held & dashboard mount devices. My Garmin Vista lets me look for the nearest food & drink, lodging, attractions, entertainment, shopping, services, transportation, and emergency & government. Most of those are subdivided, so for example on food & drink I can choose a style, under services I can search for Bank/ATM. Of course making this database costs money, which is why you have to buy it, and it's only available for major metro areas.

I have an eTrex by Garmin. It has MapSource installed, giving it points of interest data. Finding the nearest bank machine or pub or gas station is pretty cool, and has proved truly useful at times.

If anyone is interested, you can browse the maps online; e.g. Like Here

I have an eTrex by Garmin. It has MapSource installed, giving it points of interest data. Finding the nearest bank machine or pub or gas station is pretty cool, and has proved truly useful at times.

If anyone is interested, you can browse the maps online; e.g. Like Here

GPS alone has an circular error of 15 meters, or about 50 feet. With WAAS augmentation, that drops to 3 meters, or about 10 feet. WAAS only applies to the US, and southern parts of Canada. here for all the details.

Here is a link WAAS

Imbed this with a cheap GPS unit...
hate to jump on the bandwagon but... it's been done. Garmin Street Pilot III

There's one important thing to note about WAAS, however - It's currently only available in North America. More information about WAAS can be found here.

This is what happens when you allow changes into production on a Friday. NEVER change systems on Fridays, except bug fixes. Sheesh, learn some Q/A

A civilian differential GPS reciever always was able to do better than what selective availabilty should have allowed. These units gave (and still give) accuracies within 15 meters or so. Given a Loran compensation reciever (used to pick up posititioning signals meant for boats), one can improve on this accuracy by using additional known transmitters located at ground-based reference points.

If you want "new" GPS units that were recently releaesd in the past year or so, look for units with the Wide Area Augmentation System (WAAS). Implemented alongside with the FAA, these units rely on two additional satilite signals for an average accuracy of three meters.

Obligatory manufactuers links: Garmin's GPS description page and Magellan, another GPS supplier.

Actually, Garmin has one as well: Garmin.

This is true. For years Garmin has had the NavTalk but it is primarily geared toward pilots, as were most of the early civilian GPS receivers.

I hacked 6502 assembler for a few hours this weekend, to make M.U.L.E. play for whatever number of months I want it to, in CCS64 running on my laptop THEN

I went out to cheer on a friend competing in the Santa Cruz Sentinel Triathalon THEN

I went out for a 36 mile ride on my road bike, between searing heat and blasting wind, around Monterey Penninsula THEN

I went out and had a few beers and watched the Final Time Trials of La Vuelta (which Levi Leipheimer placed 2nd in and 3rd overall G.C. First American to stand on the final podium for the final Grand Tour of the season, but don't tell fscking american media outlets about it, sheesh!)

Tech geeks are increasingly athletic, many even compete in cycle racing (the most grueling sport there is) and combination events like triathlons. I'm actually in the market for rugged devices such as this, as I want to take them hiking or biking. My primary interest, atm, is one of these. So I can profile hikes and bike climbs. That is, when I'm not hacking or reading slashdot.

Andy Green would probably have something to say about me smashing his record though.

I got a Garmin Emap. I've taken it everywhere with me. The main difference is that it does mapping. (though now the more expensive etrex legend units do too)

It's about the same size and runs on 2 AA batteries. It has a backlight for nighttime use (do all of them have this?)

It has a map of all the major roads in the wester hemisphere built in, but it's expandable with the mapsource CD and it's flash memory slot (unfortunately proprietary - though it IS small).

I got it for $195 a long time ago at www.tvnav.com. It's $190 now.

The guy who runs the site also runs a mailing list that's pretty informative. Whenever a firmware or software update comes out, he usually posts a message.

The only downside is that it doesn't do any sort of routing, and neither does the $125 Metroguide Mapsource software - which sucks since that $19 AAA map software at fry's does it pretty easily. You can also get topo maps.

Last plane flight I took it on registered 620 mph (or was it 650?) at 41,000 feet.

I got one of those as well and it is an amazing device (not to mention being amazingly accurate). To be honest though right after getting my E-Trex I wished I'd gotten the eTrex Venture. Given that it includes the PC cable (which I paid extra for) it is only marginally more expensive than the standard Etrex, but it also has a city database, 1MB of memory, and 160 x 288 resolution versus 64 x 128 for the standard Etrex...well I regretted getting the basic Etrex. You can do a compare at http://www.garmin.com/cgi-bin/compare/outdoor.

I got one of those as well and it is an amazing device (not to mention being amazingly accurate). To be honest though right after getting my E-Trex I wished I'd gotten the eTrex Venture. Given that it includes the PC cable (which I paid extra for) it is only marginally more expensive than the standard Etrex, but it also has a city database, 1MB of memory, and 160 x 288 resolution versus 64 x 128 for the standard Etrex...well I regretted getting the basic Etrex. You can do a compare at http://www.garmin.com/cgi-bin/compare/outdoor.

check out the Garmin E-Trex. Besides the cheezy e-Name, it's got some very cool features. My favorite is it's ability to track your path as you walk, instead of just recording waypoints. It lets you view the path you've taken so far, which is pretty cool. The best part though? You can save that path into memory, and then retrace it. When you have the gps in 'trace' mode, the compass has an arrow on it that follows the path that you've taken. All you have to do is make sure the arrow is pointing forward. :)

Cheaper gps units can only mark waypoints (which this unit can do) but navigating between waypoints can be difficult unless you mark a LOT of them. If there's a mountain between you and that waypoint, you get to figure out how you got around it the first time, instead of just retracing your exact path.

Garmin also sells tons of accesories for their gps units. I currently have a car mount on my e-trex, as well as a cigarette lighter adapter. You can also get a bike mount, which i'm planning on doing if I ever get around to getting that mountain bike. :)

Bonus hacker points: Garmin also sells a RS232 serial cable that you can use to plug the gps unit into a computer. But that's not what's cool about it. You can use garmin's proprietary output format, or choose between about 6 or 7 standard output formats.. one of which is straight ASCII text. No reverse engineering needed.

I got my e-trex for $129 at fry's, but you might be able to find it cheaper online.

HTH

Got my eTrex today and these things are incredible (even with the tiny screen with a 64x128 resolution, though the Venture offers 160x288). Totally offtopic but just had to mention it. What a brave new world.

So in other words some things with tiny screens are amazing.

Got my eTrex today and these things are incredible (even with the tiny screen with a 64x128 resolution, though the Venture offers 160x288). Totally offtopic but just had to mention it. What a brave new world.

So in other words some things with tiny screens are amazing.

For those that don't know, SA is a set of two different time signals broadcast by the satelites. The military time signal is pure, but the civilian one had some noise injected into it to degrade the accuracy. Now that the signal degradation is no longer being done, your commercial receiver is just as accurate as the military versions.

Khadaffi | Saddam | Osama Bin Laden | Joe Militia just needs a unit from Garmin | Magellan | Trimble, and they can pick off anything in range. This has been the case for quite a while, as even with SA in use, the accuracy was about 100 FT. A good large bomb/missile has a blast radius larger than that.

Consider that the average unit only has an accuracy of 100 meters

100 meters? That must have been before 1st May 2000 when DoD lifted the scrambling of the GPS signals...

// Klaus
--

• The same price (about $195)
• Expandable, up to 128Mb carts available
• There are lots of maps including cityguide (high detail - search on nearest gas station, nearest ATM, etc...), roads & recreation and even topo maps
• It's small.

...another comment from Michael Tandy.

The garmin emap is less than $200 and displays a map.

I bought mine at http://www.tvnav.com and love it.
It's about the same size as a palm-pilot. It has
a built-in map of north and south america, but you
can spend (lots) more money on it to buy flash
memory chips and maps. That lets you download more
detailed maps along with address searches, restaurant,
hotel, services information.

I went dirt-bike riding once and I had to leave
the bike in the woods overnight. It really helped
when getting back to camp, and I wonder if I would
EVER have found my bike the next day without it.

(Sorry if this is a repost, this didn't post the first time)

This is awesome news. I use gps nearly every weekend, and it's always bothered me a little knowing that it was off a little bit.

Anyways, for more info here are a couple of links to gps sites:
GPS Info Website is an awesome starting point. Tons of links and info.
GPS and NMEA- A good FAQ site on gps in general and also hooking a unit up to other equipment (hand computer, autopilot, etc.).
US Coast Guard Nav Center has some good updates and status of gps.
Garmin- A well known gps maker, their site also has some good general info on gps (not just their units).

Anyways, have fun out there!
Jason

This is awesome news. I use gps nearly every weekend, and it's always bothered me (just a little) knowing that it wasn't as accurate as it could be.

Here are some good links to gps info:
US Coast Guard Nav Center Great status info and general policy stuff.
GPS Info Website The best central source of info on gps that I've found so far. Tons of links and content.
GPS and NMEA Site Another good source of info, including hooking up a gps to other equipment (hand computers, autopilots, etc).
Garmin A well know maker of gps units, their site also has some decent info in general on gps.

Anyways, have fun out there.
Jason

The global positioning system is a satellite-based navigation system consisting of a network of 24 orbiting satellites that are eleven thousand nautical miles in space and in six different orbital paths.

The satellites are constantly moving, making two complete orbits around the Earth in just under 24 hours. If you do the math, that's about 1.8 miles per second

I've been wanting to get a GPS receiver for my mountain biking (a.k.a. Louisiana swamp biking) adventures. Without Selective Availability (the degredation mentioned), a GPS receiver will be a lot more useful. To quote from Garmin's "About GPS" page, "Under SA, GPS accuracy can be degraded to a maximum of 100 meters (328 feet). Of course, they don't typically degrade GPS accuracy to that level, but errors of 30 meters or more are not unusual."

Obviously, having an error of about 3 meters will make finding a trail a lot easier (30 meters, being about a third of an american football field, is quite a lot of ground to cover in thick underbrush with a bike on your back while you hunt for a trail).

I can hardly wait to save up enough money to pick up my very own GPS receiver. (I am a very happy camper now.)

I'm also dying for a Garmin Moving map GPS

(All prices in USD)

Garmin GPS III Plus receiver (between 350 and 500, depending on where you buy).

Any DVD - no more than $25.

Toshiba TW65X81 or DW65X81 television to watch above dvd's - 4999 for TW, 5800 for DW.

Nokia 8860 - around 800-900

New Car - expensive

Another New Car - expensive

Luxury Car - more expensive

In lieu of computer, please send the TV. I have enough computers.

-m