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quote:Originally posted by EraSeek:SATELLITE CLOCKS ================ Each Block II/IIA satellite contains two Cesium (Cs) and two Rubidium (Rb) atomic clocks. Each Block IIR satellite contains three Rb atomic clocks. This is from the usno site and I have read several other places where they specifically state that each has four atomic clocks. I'll see if I can find them again. What did I miss there on the page? The gps display can be off if it has not caught an update in the last 12.5 mins, then it should be within about 1 sec, and the internal clock should be within a few nanoseconds. Isn't that what it says? Forgive me if I'm slow here. Eraseek, I defer... Everything I had read led me to believe that each satellite had one atomic clock. I was mistaken. I think your interpretation of the material from the website I cited is correct. I think the discussion at this time might be somewhat dated--that receivers nowadays keep track of the leap seconds, and that they also display correct time (within about 1/10 second) once the satellites have been all acquired. However, I believe my main point stands--of what benefit is it (other than bragging rights) of having a clock accurate to 200 nanoseconds (or what ever) when it is only displaying full seconds.

I will tell the cacher about incorrect coords if they are significantly off. If what he posted (his 40° 37.260 111° 51.200 yours 40° 37.259 111° 51.195) were correct, those are only off by 23.86 feet - much less than the error that you would get from a GPSR. Why bother, you could be off by 20 feet and he could be off by 20 feet. I think getting that close is pretty darn good. On the other hand, if it had been off by 100 or 150 feet, that's worth considering, and I (as the cache's owner) would want to know. But why bother with telling people their coords are off when you could be incorrect, also, and they very well both could be off? It does make you sound a little elitist - but I wouldn't have responded so curtly as he did.

quote:Originally posted by wizmedic:... Well, this morning, I got this email: "Wiz. Check my coords? You must be up there in the geo social circle to even suggest it. Lets compare: mine 40/37.260 111/51.200 yours 40/37.259 111/51.195 Notice that both my lat/lon end in zero? Ever heard of Magellan Pioneer? (it's older than some children in this sport) WAAS? Get real. Sorry if you the one to catch the brunt of my wrath, but I am sick of the "elitist" attitude I have been getting from many (almost all I encounter) in this sport. Instead of upgrading my equipment I am ready to drop geocaching altogether. (handle name)" ... I would not lose too much sleep over it. I think you did the right thing and that person was a jerk for sending you mail like that. Maybe they woke up on the wrong side of the bed and had a bad day/week/month.... I see many people post updated coordinates on cache pages as a courtesy to the next cache hunter. I have posted updated coordinates without suggesting the cache hider update them. I simply point out when I found it, I was at x.xxxx / x.xxxx. It really is a bummer to hunt and hunt only to find the original coordinates were not accurate. He should "get real" and lighten up. Funny how he points out attitude.... ------------------ Brian & Terry San Diego, CA [This message has been edited by bridaw (edited 28 August 2001).]

quote:Originally posted by wizmedic:... Well, this morning, I got this email: "Wiz. Check my coords? You must be up there in the geo social circle to even suggest it. Lets compare: mine 40/37.260 111/51.200 yours 40/37.259 111/51.195 Notice that both my lat/lon end in zero? Ever heard of Magellan Pioneer? (it's older than some children in this sport) WAAS? Get real. Sorry if you the one to catch the brunt of my wrath, but I am sick of the "elitist" attitude I have been getting from many (almost all I encounter) in this sport. Instead of upgrading my equipment I am ready to drop geocaching altogether. (handle name)" ... I would not lose too much sleep over it. I think you did the right thing and that person was a jerk for sending you mail like that. Maybe they woke up on the wrong side of the bed and had a bad day/week/month.... I see many people post updated coordinates on cache pages as a courtesy to the next cache hunter. I have posted updated coordinates without suggesting the cache hider update them. I simply point out when I found it, I was at x.xxxx / x.xxxx. It really is a bummer to hunt and hunt only to find the original coordinates were not accurate. He should "get real" and lighten up. Funny how he points out attitude.... ------------------ Brian & Terry San Diego, CA [This message has been edited by bridaw (edited 28 August 2001).]

That is correct as far as it goes. The receiver does generate extremely accurate time for its position calculations. However, receivers may or may not display that accurate time on the unit itself. I've read that on some (older?) units, the time displayed may be off by as much as nine seconds. The other problem is that most readouts only read to one second. It takes a mighty sharp mind to mentally subdivide that out to 200 nanosecond divisions. Here's what I would do. Check the readout against a known accurate source (WWV, commercial broadcast, etc. That should give you some idea of its accuracy.

That is correct as far as it goes. The receiver does generate extremely accurate time for its position calculations. However, receivers may or may not display that accurate time on the unit itself. I've read that on some (older?) units, the time displayed may be off by as much as nine seconds. The other problem is that most readouts only read to one second. It takes a mighty sharp mind to mentally subdivide that out to 200 nanosecond divisions. Here's what I would do. Check the readout against a known accurate source (WWV, commercial broadcast, etc. That should give you some idea of its accuracy.

Once the GPSR syncs to 4 or more satellites its clock will be adjusted to the correct time within about 200 nanoseconds. See http://celia.mehaffey.com/dale/theory.htm or http://www.howstuffworks.com/gps1.htm A lot more accurate than any watch you might have.

I looked and all the big sporting goods stores here in Albuquerque do not have outlets in Indiana / Ohio. Check your yellow pages for sporting goods stores that carry hiking/camping/hunting equipment. There are two REI outlets in Chicago, though. Even discount stores like Wal-mart Kmart and Target will let you read the boxes and maybe take the unit out and read the manual. I just wouldnt expect much expert knowlege about GPS units from one of those employees. It has been my experience that for every one you find that might actually know what they are talking about, you run into three or four that have no clue, but often confidently give false info. The flip side of that is one can usually return a product to a department store with no hassle if it doesnt meet your expectations. I have a Garmin III+ that I would highly recommend. They can be found on the internet for as little as $240. I realize that is out of your stated price range, but most GPS units that allow you to load maps into them are in at least that price range neigborhood. If you can find a regular Garmin III they should be less than $200. The only real difference is the + lets you buy additional software (about another $100) so you can download more detailed maps. Both units have a built in basic roadmap. (highways and MAJOR city streets) I also have a Magellan Blazer 12 and an Eagle Explorer. I wouldnt recommend either of those for Geocaching. Best bets for cheap would be the basic yellow E-trex or the Magellan 315. I think both of these are available for less than $130. (I saw the E-trex for less than $110 somewhere) Whatever you do be sure that you can enter lat long minutes to 3 decimal places! The cheapest units only let you enter two, which technically increases your search area by a factor of 100! (realistically it isnt quite that high) Here is what I said to someone else in your same situation on another thread: http://forums.Groundspeak.com/ubb/Forum1/HTML/000368.html good luck, and any more specific questions, please ask! Someone here will know the answer. [This message has been edited by Gliderguy (edited 25 August 2001).]

You guys got me going on these theme ideas. I am planting one tommorrow called "Ye Olde Pirate Treasure" Here is a sample of the write up: Arrrrrrrgggh ..... Mateys!, it is I, Cap'n Paul here. I have been secretly passéd ye map coordinates to give ye from one of the Blackbeard crew. Shhhhhhhhhh !!!! Not a word or ye will only end up being flogged, keel hauled, or having ye throat cut by those thievin', crimson coated, yellow-bellied, villainous pyrates and buccaneers. It is so sweet, I got this wooden treasure chest, put 288 fake gold coins in it with a log book that looks 200 years old. I am pumped up. I will post link with pic later.

quote:Originally posted by Markwell:They're not always like that. Some of them are in capped PVC tubes, some are watertowers. Make sure you download the detail sheet and print it off and read the descriptions they give (also make sure you convert from DDMMSS to DD MM.MMM). I've found three so far, just to pass the time. It's kinda fun while waiting for more caches to be placed - since I can't get out and hide on my lunch hour. I read this thread just before leaving the office, identified a target, and saw my first survey marker disc on the way home from work. It was on the side of a grain elevator in an older part of town. The details of the record showed the coordinates in a HDD:MM:SS format, and that they had been derived from topo maps. I was disappointed at first when I walked right up the marker and my Etrex said I still had 200 feet to go! Later, at home, looked closer at the report and saw that it said the coordinates were accurate to +/- 6 seconds. I crunched some numbers on this and found that a difference of 6 seconds means about 600 feet! Now I just need to find some markers with a higher degree of precision. The only problem is that most of the ones in my area are in restricted areas like airport runways, under radio towers, along the interstate, etc. This looks like a great thing to do between caches. BTW: I wouldn't worry about converting from one format to another. If other GPSRs are like my Etrex, you can just change the format of the receiver to suite the coordinates in the data record.

quote:Originally posted by Markwell:They're not always like that. Some of them are in capped PVC tubes, some are watertowers. Make sure you download the detail sheet and print it off and read the descriptions they give (also make sure you convert from DDMMSS to DD MM.MMM). I've found three so far, just to pass the time. It's kinda fun while waiting for more caches to be placed - since I can't get out and hide on my lunch hour. I read this thread just before leaving the office, identified a target, and saw my first survey marker disc on the way home from work. It was on the side of a grain elevator in an older part of town. The details of the record showed the coordinates in a HDD:MM:SS format, and that they had been derived from topo maps. I was disappointed at first when I walked right up the marker and my Etrex said I still had 200 feet to go! Later, at home, looked closer at the report and saw that it said the coordinates were accurate to +/- 6 seconds. I crunched some numbers on this and found that a difference of 6 seconds means about 600 feet! Now I just need to find some markers with a higher degree of precision. The only problem is that most of the ones in my area are in restricted areas like airport runways, under radio towers, along the interstate, etc. This looks like a great thing to do between caches. BTW: I wouldn't worry about converting from one format to another. If other GPSRs are like my Etrex, you can just change the format of the receiver to suite the coordinates in the data record.

quote:Originally posted by Kerry:There is probably a better term that describes 2 feet but it's certainly not accuracy and one certainly won't get that type of accuracy out of a $200 handheld. I think the word of that day was "lucky." Two discussions going on here: How did I get my GPS to read that accurately? Dumb luck. More precisely, I think there was a combination of errors that produced a remarkable result. I've never had that kind of accuracy before or since, so I can't vouch for the accuracy or precision of my unit. But it sure felt good! How did I get my GPS to read in "feet?" See earlier post - firmware automatically does that for me.

quote:Originally posted by Kerry:There is probably a better term that describes 2 feet but it's certainly not accuracy and one certainly won't get that type of accuracy out of a $200 handheld. I think the word of that day was "lucky." Two discussions going on here: How did I get my GPS to read that accurately? Dumb luck. More precisely, I think there was a combination of errors that produced a remarkable result. I've never had that kind of accuracy before or since, so I can't vouch for the accuracy or precision of my unit. But it sure felt good! How did I get my GPS to read in "feet?" See earlier post - firmware automatically does that for me.

nce. how does Markwell do it? Not sure but maybe being a little optimistic helps. Gee even the new Block IIR's (and there's only about 6? of them all up) have a signal in space error of about 0.75m and that's before the atmosphere gets hold of it. There is probably a better term that describes 2 feet but it's certainly not accuracy and one certainly won't get that type of accuracy out of a $200 handheld. Cheers, Kerry.

Sounds like researching the topo info for the area of the cache would help. I am the worst person to talk about it, but tracking down as much information in advance a possible can really make caches a lot easier. I have been within 200 feet of a cache found a river between the cache and me. Had I bothered to grab a street map, and a topo map I could have had easy parking near the cache, and short walking distance. That said, we really could use a more descriptive terrain option. Something like how some movies will say "Rated PG-13 for brief nudity", we could have "Rated 1.5 for short steep hill". It is possible to do that now in the description, but it is completely subjective. Maybe have a disable checkbox? I think even just mentioning in the cache placement FAQ to keep this in mind when writing a description for a cache would be a big help. Dan

Pre for me too. Had an Eagle Accunav as my first unit. It would eat 6 AA batteries in about as many hours! As my name implies, I used it for keeping tabs on the home field when flying a sailplane. it was SO reassuring to know the exact mileage and be able to rough out a wind strength. I finally did a few cross-country flights with it, to date my longest was 76 miles. (the real pros can do over 1000 mile days in ideal conditions, and 200-300 mile days consistently)

I use Lithium batteries, Regular alkalines, and External Batteries. I have used Rechargable alks lot, but that was before my GPS days. I remember it saying on the Rayovac Renewal Battery packaging, that thay can last longer if not depleted. I would like to comeup with a battery holder that can clip onto my Etrex Vista or the 3plus, that can hold an extenal battery pack. Also the Vehicle Power adaptor cable can come in handy. I bought from Radio Shack, a cable that clips onto any 12 battery, and on the end of the Vehicle power adaptor cable. Just need a pocket to carry the battery in. One way i could do it, without voiding the warrenty on the Etrex Vista is to order a replacement battery door, and modify it to allow recarging of the internal batts. Would be nice if i could trickle charge the batts, without removing them from the GPS. One advantage of the low voltage Etrex Vista, is that somebody could come out with a 200 milliamp 3volt SolarCell that can clip onto the Vista. I do have the 3plus, a Vehicle power cable, a 12volt battery, and a cable to go between. Works pretty good, except one problem, if there is a break in the connection, the GPS will shutoff in 30 seconds. [This message has been edited by Geoffrey (edited 17 August 2001).]

Does anyone know of a program that will import waypoints from a plain text file? I have about 200 lat/lon waypoints in a text file formatted like this: WPTNAME, NDD MM SS, WDD MM SS, DESCRIPTION,... I would like to suck these into a program that can load them onto my Garmin GPS. Mapsource will import PCX5 data -- but what I have is essentially a list. Mapsource can also export a text file, and I could format my list like that, but it has no provision to import a text file! I can format the list pretty much any way required. Any ideas? [This message has been edited by ekobres (edited 17 August 2001).] [This message has been edited by ekobres (edited 17 August 2001).]

My 330 does the same thing at home, about 200 ft. off from where the map shows my house to be. I'm usually within 12 ft. of the geocaches I've found so I assume the error to be in the map.

The Magellan 315 says it comes programmed with coords for large cities around the world. I was hoping to be able to call up a city far away and have it goto and be able to say london is x miles that a way. but all I can see are cities on the east coast (I am in NY). is there something in it that lets you access only locations that are < 200 or some other number of miles away? thanks!

quote:Originally posted by paulb:Well, I stumbled upon your world of hitech hide and seek. After hiking down to a beautiful dry ravine, we noticed a series of carved "cliff dwellings" chopped into the face of a canyon about 200 feet away from the end of the trail...curious, and amazed, we headed over to them, and discovered your cool fun. The guest book had been signed as recently as yesterday, and all items appeared in good order. I took some really great photos of the caves, and I'll try to get them posted somewhere. Great idea, it brought a beautiful hike into the age of communication. Rock on, We were the family that posted on the 5th paulb. We hid it with rocks and tried to keep it from view....guess we didn't do so well....hehehehe. Did you take the traveler??? or any of the other items? I emailed the owner of the cache and he is going out to take care of the cache. There was no container left, just baggies. Thanks for posting your find.....Aloha!

By Model -------- Magellan 315: 21 Garmin eTrex Legend: 20 Garmin III+: 19 Garmin Vista: 18 Garmin GPSMAP 76: 15 Garmin eTrex: 14 Garmin 12: 13 Lawrance Globalmap 100: 13 Magellan 330: 12 Garmin eTrex Venture: 8 Garmin 12XL: 5 Garmin eMap: 5 Garmin eTrex Summit: 4 Garmin 12MAP: 4 Garmin III: 2 Magellan 2000XL: 2 Eagle Accunavsport: 2 Magellan for HandSpring: 2 Lawrance Globalmap 12: 2 Garmin III Pilot: 1 Garmin GPS 76: 1 Garmin eTrex Mariner: 1 Garmin 48: 1 Garmin 45XL: 1 Magellan 320: 1 Magellan 330m: 1 Magellan 410: 1 Magellan 2000: 1 Lawrance Globalmap 200: 1 Lawrance Globalmap 212: 1 GeoDiscovery Geode: 1 Apelco/Ratheon GPS11: 1 Eagle Explorer: 1 Silva Multi Navigator: 1 By Brand -------- Garmin: 132 Magellan: 42 Lawrence: 17 Eagle: 3 Apelco/Ratheon: 1 Silva: 1 mcb

quote:Originally posted by Jebediah:I think that requirement isn't based on decomposition rates but rather on the extremely limited amount of dry accessible soil in certain sensitive canyon areas. Imagine what would happen if everybody defecated in the same sand bars and pull-outs hundreds of times a season. It's a combination of visitor volume and the environment's limited ability to absorb the amount of waste being generated. Desert decomposition rates are so slow that some archaeologists have studied 900 year old sun-baked feces to bolster the claim that the ancestoral Pueblos (Anasazi)practiced ritual cannibalism. Back on topic: For most environments, Leave No Trace says: "Deposit solid human waste in catholes dug 6 to 8 inches deep at least 200 feet from water, camp, and trails. Cover and disguise the cathole when finished." (There are different recommendations for western river corridors and desert canyon country.) Since the Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service and U.S. Forest Service are all federal partners in the LNT programs, it strikes me that Mary Pat's initial post was more anti-geocaching than anti-digging. In no way would I ever condone the burying of geocaches, but the bold assertion, "Digging or disturbing land in National Forests is illegal!" just doesn't make sense. Her further assertion that my observation regarding standard backcountry sanitation was a failure of logic, her continued threats of arrest and fines, along with her failure to address the specifics of the law only confirms my belief that she is the type of lower level government employee that is best avoided; "Yes, Sir", "No, Ma'am" and move along without questioning their authority. I'm sorry I ever jumped into this thread. In the future I'll limit myself to discussions with policy makers and managers. Cephas Hawke Bedford, NH [This message has been edited by CaptHawke (edited 08 August 2001).]

My ancient Garmin GPS 38 is on its death bed and I've got 200 waypoints stored in it. I'd like to move them to my PC, but I don't have a cable for it and I really don't want to spend $35-40 on a cable I'll only use once. Is there anyone in San Diego with a suitable cable that can help me?

arffer, I noticed that the topo maps are very old. but using the mapblast with the software really fixes that. but i still want the detailed base maps on my legend which will cost me almost $200 for the Garmin mapsource CD and want to buy the newest one that will be out this month. I might figure I can just get by with this software $200 is alot. I'm just so torn on what I should do. Might just get the rods & rec mapsource on eBay for $60..don't really need the address capabilites when the rd&rec CD has all the city streets any way, but then address at my figer tips would be nice...dadgum torn already again..think I'll think about it! ------------------ Bought a eTrex Legend on 7/24/01 placed one cache Here --HomeChicken