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Everything posted by geckoee

  1. Wow! How do you do that? I decided to buy it for the waypoint, track log and route managing, and the maps.
  2. With USA Photo maps you can do that for free (but a small donation is suggested) or with Expert GPS for $60. Expert GPS has the same waypoint manager as Easy GPS and a very nice track manager. <edit> Expert GPS doesn't have the altitude profile image but you can export the data to excel making it very easy to create all sorts of charts and statistics. i.e. calculate average climb rate, map position vs. altitude for a 3D view of the trail etc. I'm not saying Expert GPS is better. For $40 more it looks like Tahosa and Sons got some nice extra capabilities! </edit>
  3. mrkablooey has a good point. The "Geocaching.com Maps" are a good tool for this. (Found on every cache page) They show most park boundaries, and all the caches that are in the area.
  4. I've had that problem as well while downloading .loc files, but I use different software to open the files. I also use two different computers, but mine are windows XP and windows 200 pro. To fix the problem I logged out of gc.com and then logged back in. It's a strange problem, and I really don't know what may be going on here. I'm glad to hear I'm not the only one seeing this. Maybe the ever so nice Groundspeak people will look into it.
  5. Or the day the first cache was released on sci.geo.satellite-nav May Third 2000.
  6. 24 hour cycles. Trimble has all you need to know about satellite configuration. Download the Trimble Planning software. It shows you satellite coverage, and times for best reception etc. There web site also has a good All about GPS section.
  7. The "King's Leap" has many meanings to different people. From a chess move that has been removed from the game, to a King who leaped a mile to impress Buddha, but didn't leave the palm of Buddha’s hand. This story has also been re-told as “The White Monkey King.” Just trying to say that the term "King's Leap" may be a little vague.
  8. Next to and there is a button for You can edit it to say "never mind" or something equally inconsequential.
  9. Is that heading in degrees from magnetic north or grid north?
  10. geckoee

    Easy Gps

    Sounds to me like it might be a file association problem. The .loc and .gpx file format is similar to a format used to display data on web pages (I want to say XML but I'm not sure on that.) If you (right click and) save the .loc files to the desktop is the icon the friendly yellow smiley or something else? You may have to change the file types of some of the "helper" files in ie or netscape too, but I don't remember how to do that either. I hope that was some help. I'll keep looking around for some more info. edit for right clicky thing.
  11. If your GPSr does not have a magnetic compass (or you have it turned off) when walking slower than about 1mph the bearing indicator may point the wrong way. Dial up the bearing on a pocket compass, match the north indicators, and follow that for the distance indicated on the gpsr.
  12. Once again it is ground down to presentation being everything. Whether it has substance or not, without proper appearance it is worthless. Sad, but true me thinks. Edit for grammar
  13. There is no need for 'spell check.' We can review our writings prior to posting them. If an error slips through, we have the ability to edit the post. Everyone makes mistakes, and I find the occasional misspelling to be neither distracting nor offensive. Posts replete with misspellings are another matter. The misspellings are often an excellent indication (or warning) of the overall quality of the post. 'A rose by any other name might smell as sweet,' but I see neither reason nor advantage to using a spell checker to 'polish s**t.' ...So a bad speller is a bad writer? Are you also saying if my post is poorly written it should not be as valued as a well-written post?
  14. Funny stuff. RockClimbing.com has the same Forum managing software, and they have an integrated Spell check. It clears up a lot of problems.
  15. For GPS realted averageing check out GPS Accuracy
  16. I hear Garmin makes a fish finder that is good for TROLLING!
  17. Artman, I’ve only been able to find vertical stations near my area. There are some triangulation stations, but I can’t park a GPS on it for over two hours unless I sit there and watch it the whole time. I’m procrastinating, but I can’t get away with that much Renegade Knight, good point. Trogdor, I think you answered your own question. The idea is to get a more precise reading from something that is not that precise. Also, thanks for explaining accuracy vs precision I left that out of the post, but I guess it’s needed in case some one is un clear on the concept. briansnat, The idea is that if you have a large enough continuous data set the average will be close to the real. Coordinates tend to walk about 20 feet around the real location in 45 mins. If you average all of those points, or a little smaller sub set you will get a result that is close to the real. Keep in mind this is a small sampling of data, and all of it was collect when the satellites were in an optimal geometric configuration. I may not have go into enough depth about what a rolling average is, or the patterns of walking position reported by a GPS. Oh well, I’m not going to go into it. Also it might not be practical as it turns out for Geo-caching, but an interesting line of thought any ways. Edit to clean things up a bit. It gets dirty on the first read through
  18. You're right about the variation being under test, not really the accuracy. The average of the data was used as the "real" location. From topo maps, aerial photos, and bearings to nearby targets it is pretty close, but that can only get you within about a meter. Considering the variation was up to 20 feet I guess it is relatively close to the real position. After collecting the data, and analyzing it, I feel I have a better understanding of GPSr location data, and how to use it. Thanks for the feedback.
  19. Yet another way point averaging thread. I have been asking myself this question for a while, and seen other people ask, and seen answers as well. There are some good links out there that people have referenced, but from a geo caching perspective I wanted a clearer answer. Definitions as used in this question: correct coordinates – known accurate to 0.001 minutes as observed by a Garmin ETrex Yellow. This model was chosen as a rough approximation of the standard 12 channel consumer GPSr. Two common answers: 1. Average waypoints over a time interval (usually people suggest 5 to 10 minutes) 2. Take multiple waypoints on different days at different times. 1.5. Do both. Average over a time interval at different times throughout the day. The question remains; how long must I average for? and how many way points? Background understanding: Satellite geometries at any specific location repeats on a 24 hour cycle. This makes different times during the day important when way point averaging. GPS locations reported by a consumer receiver “walk about” and don’t jump sporadically. This has to do with atmospheric effects, satellite geometry, the mechanisms employed in the GPSr software to create a position, as well as other factors. By zooming in on data being collected by a programs (such as ExpertGPS, GPS Trackmaker, or any other program that displays NMEA or similar data, ) this can be observed. The DD MM.mmmm NMEA format was chosen over UTM because of the higher resolution. On the display of our GPSr we are used to seeing 3 digits of precision after the decimal point, but NMEA actually sends out 4, or a resolution of about 7 inches. This is about five times higher than UTM. Set Up and Analysis: GPS was placed on the dash of a passenger vehicle. A car was chosen for it ability to be placed out in the open and have the content of the vehicle securely locked. This particular vehicle was chosen for its large slanting wind shield, for a better satellite view, and lack of polarization or tinting, so signals are not disturbed too much. Data collected using ExpertGPS and ported over to MSExcel for data analysis. Results: Worst case average precision (50%) No average 0.00654 0.00131 5 min average 0.00470 0.00106 10 min average 0.00300 0.00095 20 min average 0.00188 0.00074 30 min average 0.00154 0.00068 5 point average 0.00208 0.00059 10 point average 0.00151 0.00057 5 10 min averages 0.00219 0.00107 Explanation of Results: All data is in Minutes. At my location the majority of the error was in latitude. These definitions get a little rambly. 5 min average is a rolling average over 5 minutes. The 10 to 30 min averages are rolling averages over 10 to 30 minutes. The 5 point average is 5 waypoints taken about 2 minutes apart (worst case and average precision are derived from similar rolling average methods) The 5 10 min average is five different 10 minute averages, all average together. Conclusion: Method 1: 0.001 minute resolution requires over a 30 minute average, but most of the time a 5 minute average will suffice. Method 2: Ten waypoints averaged through the day yields nearly 0.001 accuracy. Method 1.5 Five averages of 10 minutes will get you close most of the time. The data used for these calculations was very limited. Only 4500 data points, 2 seconds apart were collected. All data was collected during a 2 ½ hour ideal geometric configuration as determined by Trimble Software. I would be curious to see what data other people have collected in other locations… or know if someone actually read this far! If you want to see the raw data, drop me a line, and I will email it off to you. Edit to clear up the table a bit
  20. I think most people reading this thread know who knows there stuff, and who doesn't know what type of math they are useing.
  21. This may be a little off the Geo-caching topic, but does any one know of a good campsite listing? Microsoft Streets and Trips has a few, and there is AAA, but how about a more comprehensive listing? I'm thinking online, software, or a book. Also how about regulations on off trail camping. Some parks, such as Joshua Tree National Monument in CA and White Mountain National Forest in NH, allow you to camp as long as you are not in site of a main trail. (I’m using the work “park” pretty loosely here.) Any one have resources to report? edited to add NH.
  22. I think you are looking for PV=nRT Where P is pressure, V is volume, n in the number of mols of gas, R is the universal gas constant and T is temperature in Kelvin. n, R, and V are constant, so pressure is directly proportional to the change in temperature. So The pressure is 1-(303/252) times lower, or 20% lower. F=Delta(P)*area F = (0.20*15)*72 = 216 lbs of force! That’s assuming you are pulling strait up. If you are prying it off you have about a 2:1 advantage. That's what the brain does when you go back to school. 1 ATM = 15 psi 30x15cm lid = 12 x 6 inches = 72 square inches. The starting temperature was about 90°F which equals 303°K That's T1. The ending temperature was about -5°F or 252°K. That's T2.
  23. Sign me up for one of those! When I die I want my house to die with me! ... please!
  24. Simple answer: No. Complex answer: The voltage of recievers has no impact on the signal received. That onus is on the transmitter. You can however use an amplified antenna, which would boost the strength of weak signals--but your GPS accuracy is not affected by power levels. Enjoy, Randy (Sorry General, our smart bomb didn't fly down the chimney because Private Reed was using the batteries in her, um, er, personal appliance last night.) I trouble shoot antennas, and microwave signal processors, so I like to pretend I know what I am talking about After the signal is received by the antenna sometimes there is some passive processing done to it to limit the band, and determine the phase and possibly other things. At some point the signal needs to be amplified in order to be interpreted by the MCU. (sometimes this amplification is done before processing) A lower voltage level means a smaller window for measurement, and more background noise. So voltage level has some, but limited impact on signal integrity. Check out this URL for more info. The first stage after the antenna is a 10dB gain amp!
  25. Resetting the firmware shouldn't require a trip back to the factory. Under certain circumstances, it could cause it to become miscalibrated, but if you do it indoors, where it can't get a signal, you don't have to worry about that. The unit will recalibrate itself over time. You will, of course, have to reload any OS upgrades, waypoints, routes, etc., as they will be lost. You'll also have to reacquire almanac data, as well. Yeah it looks like a trip back to Garmin may not be nessisary, Garmin dose say on there web page not to load the wrong firware as that can hose the unit. 3rd Party FAQ Garmin Info
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