Beermaker Posted November 12, 2006 Share Posted November 12, 2006 First post here. I recently decided to give geocaching a try and bought a used E-trex legend to start out with. I have yet to venture out into the woods to look for a cache but thought the gps would be a good way to track my progress on bike rides I take for fitness. On a recent ride I pull it out about halfway through to check mileage, ave speed etc, everthing looked good until I got to max speed, 140 mph!!! Huh? thats pretty fast (I had cleared the data beforehand). I put it back in my pocket and finished the ride. I checked it again and it now gave max speed as 208mph!!! Wow I must be the fastest person on a bike in the world.... Or there is some kind of glitch in my gps unit. What would cause these numbers? Quote Link to comment
+Airmapper Posted November 12, 2006 Share Posted November 12, 2006 It is caused by poor reception, with your unit in your pocket like that it tends to "jump around", as in it's position is not steady. This jumping makes the unit think you went from one point to another at a high speed. Quote Link to comment
+markp99 Posted November 12, 2006 Share Posted November 12, 2006 Beermaker, You neglected to tell the whole story: Quote Link to comment
+Lasagna Posted November 12, 2006 Share Posted November 12, 2006 eTrex Legend in your pocket ... pretty sure you've likely lost satellite coverage. In that case, when it finally regains coverage, it may have appeared that you jumped a pretty good distance in a very short period of time. Keep the Legend out of your pocket ... get a handlebar mount or wear it around your neck (although I've lost signal that way too when the patch antenna isn't facing toward the sky). Quote Link to comment
Beermaker Posted November 12, 2006 Author Share Posted November 12, 2006 Beermaker, You neglected to tell the whole story: Nawww, this is my bike Thanks for the explanation on the gps error, I will try a handlebar mount and see if that helps. Quote Link to comment
+Green Achers Posted November 12, 2006 Share Posted November 12, 2006 On a recent ride I pull it out about halfway through to check mileage, ave speed etc, everthing looked good until I got to max speed, 140 mph!!! Huh? thats pretty fast (I had cleared the data beforehand). John Howard? Is that you?? A 140 doesn't keep up with the world's fastest bicyclist. Interesting that I was talking to him after he came back with this title... he also set the worlds record for the fastest moving bicycle to get a FLAT TIRE too! Turns out the wheels were turning so fast, the air valve springs where compressing!! After repeating this twice, a motorcycle racer figured out the problem. He changed to 'presta' valve tubes and the rest is history. World's Record Oh, you're error happens I believe when your GPSr thinks it's at one location and then discovers it's really in another... the rate that it changes this can be calculated into miles per hour. When my Garmin 60csx first did this, I sat $ATM$ down and explained she was not allowed to see how fast she could drive. I showed her my proof that she had gone lawless and she laughed at me. Quote Link to comment
rickertk Posted November 14, 2006 Share Posted November 14, 2006 As far as the GPS in a pocket goes, was it a shorts pocket or a jersey pocket? If it's a shorts pocket, I agree that reception is likely to be poor there. I've had very good reception in a jersey pocket facing outwards though, or inside my Camebak when I'm riding with that. Around the neck is going to be facing the wrong way on a bike. Handlebar mounts are the best for seeing the GPS while riding, although with my GPS I have to be careful not to jar it too much. Keith Quote Link to comment
+rstickle Posted November 14, 2006 Share Posted November 14, 2006 I put it back in my pocket and finished the ride. I checked it again and it now gave max speed as 208mph!!! Wow I must be the fastest person on a bike in the world.... Or there is some kind of glitch in my gps unit. What would cause these numbers? Ahhhh, That's not so great. I was WALKING in the woods with mine once and clocked 300+ MPH! (That's when I decided it was time for a change - to 60CSx!) Rick Quote Link to comment
Neo_Geo Posted November 14, 2006 Share Posted November 14, 2006 (edited) I put it back in my pocket and finished the ride. I checked it again and it now gave max speed as 208mph!!! Wow I must be the fastest person on a bike in the world.... Or there is some kind of glitch in my gps unit. What would cause these numbers? Ahhhh, That's not so great. I was WALKING in the woods with mine once and clocked 300+ MPH! (That's when I decided it was time for a change - to 60CSx!) Rick Pshhhhhh... I got y'all beat! I was just STANDING on a street corner : Edited November 14, 2006 by Neo_Geo Quote Link to comment
ossumguywill Posted November 15, 2006 Share Posted November 15, 2006 I put it back in my pocket and finished the ride. I checked it again and it now gave max speed as 208mph!!! Wow I must be the fastest person on a bike in the world.... Or there is some kind of glitch in my gps unit. What would cause these numbers? Ahhhh, That's not so great. I was WALKING in the woods with mine once and clocked 300+ MPH! (That's when I decided it was time for a change - to 60CSx!) Rick Pshhhhhh... I got y'all beat! I was just STANDING on a street corner : Wait.. I thought civilian units only tracked up to 950 mph due to sat restrictions or something.. is this not true? Quote Link to comment
saw-saw Posted November 15, 2006 Share Posted November 15, 2006 I have had a lot of erratic readings on my GPS, upload the the tracks and take a look at them they are also interesting. I agree they are caused by loosing reception and then regaining reception at or near the same point. Quote Link to comment
Neo_Geo Posted November 15, 2006 Share Posted November 15, 2006 Wait.. I thought civilian units only tracked up to 950 mph due to sat restrictions or something.. is this not true? I cannot answer whether or not it is true, but this was not a true track. It was an anomaly. Quote Link to comment
ossumguywill Posted November 17, 2006 Share Posted November 17, 2006 (edited) Wait.. I thought civilian units only tracked up to 950 mph due to sat restrictions or something.. is this not true? I cannot answer whether or not it is true, but this was not a true track. It was an anomaly. Yes but a government webpage I found said that civilian receivers would only give a reading of up to 950 mph so that gps couldn't be used on makeshift missiles. hmmmmmmm....... maybe they meant that the civ. gps sats would only give a true reading of 950 mph. Edited November 17, 2006 by ossumguywill Quote Link to comment
Suscrofa Posted November 17, 2006 Share Posted November 17, 2006 (edited) Wait.. I thought civilian units only tracked up to 950 mph due to sat restrictions or something.. is this not true? I cannot answer whether or not it is true, but this was not a true track. It was an anomaly. Yes but a government webpage I found said that civilian receivers would only give a reading of up to 950 mph so that gps couldn't be used on makeshift missiles. hmmmmmmm....... maybe they meant that the civ. gps sats would only give a true reading of 950 mph. The speed displyed on the GPS is computeded from the time it takes to move frm one position to an other one, I can't see how then, the gov. can prevent the speed computation. If the limitation is built in the GPS, keep in mind that ther are two kind of mph (even three kind of miles !), the US mph and the nautical mph, so what is displayed in this peculiar case is below 950 knots. Edited November 17, 2006 by Suscrofa Quote Link to comment
+Train_Man Posted November 17, 2006 Share Posted November 17, 2006 I once had a Legend and hit 1657mph (beat that!) at an all-day event in the snow with the unit in my backpack all day. That track log was CRAZY lol. Sure wish i thought to get a screenshot Quote Link to comment
+W4G_SOTAGoat Posted November 17, 2006 Share Posted November 17, 2006 A friend was on a road trip to SC and his StreetPilot clocked him at 181mph. He bragged about it for months and finally cleared the Max Speed after about 6 months. Quote Link to comment
+BigLarry Posted November 19, 2006 Share Posted November 19, 2006 The eTrex have a patch antennae that works much better when the screen is facing straight up at the sky. If you get a handlebar mount, this is the correct position, and you can use it while riding too. The handlebar mount also moves it away from your body, which will block satellite signal. Your overall reception will dramatically improve, and you can read your GPS while riding. Don't worry about the eTrex being damaged by your riding with it on the handlebars. I have an eTrex Vista on the handlebars for 3 years through all sorts of nasty mountain biking with frequent big hit through rock gardens and fast downhill. My frame has broken three times, as well as many, many crashes. The eTrex survived all fine, with just the normal wear and tear. Quote Link to comment
ossumguywill Posted November 22, 2006 Share Posted November 22, 2006 Wait.. I thought civilian units only tracked up to 950 mph due to sat restrictions or something.. is this not true? I cannot answer whether or not it is true, but this was not a true track. It was an anomaly. Yes but a government webpage I found said that civilian receivers would only give a reading of up to 950 mph so that gps couldn't be used on makeshift missiles. hmmmmmmm....... maybe they meant that the civ. gps sats would only give a true reading of 950 mph. The speed displyed on the GPS is computeded from the time it takes to move frm one position to an other one, I can't see how then, the gov. can prevent the speed computation. If the limitation is built in the GPS, keep in mind that ther are two kind of mph (even three kind of miles !), the US mph and the nautical mph, so what is displayed in this peculiar case is below 950 knots. I just double-checked. The government has a requirement that civilian gps receivers can only report up to 950 mph even if your acual speed is a billion mph. Maybe the version of firmware you guys had didn't have limits programmed in accidentaly. Quote Link to comment
Neo_Geo Posted November 22, 2006 Share Posted November 22, 2006 (edited) Do you have a link or URL to the gov't information? Perhaps it's a recent requirement whereas my reading happened back in 2002 I think. Check THIS out. Mine was on an eTrex Legend, and this one was someone else on a yellow eTrex! He's got me beat 4 times over Edited November 22, 2006 by Neo_Geo Quote Link to comment
ossumguywill Posted November 23, 2006 Share Posted November 23, 2006 Do you have a link or URL to the gov't information? Perhaps it's a recent requirement whereas my reading happened back in 2002 I think. Check THIS out. Mine was on an eTrex Legend, and this one was someone else on a yellow eTrex! He's got me beat 4 times over Somewhere here. Quote Link to comment
+GOT GPS? Posted November 23, 2006 Share Posted November 23, 2006 (edited) I have been into GPS technology since 1998, and I been buying Garmins and Magellans since then. The Government requires that a consumer GPS cannot ACTIVELY track any moving object faster, or higher altitude than government imposed limits, so that you cannot mount a GPS on any missles you may have lying around your house. Magellan's imposed speed limit is down to 951 mph, which is well bellow 1000knots(1150.78mph), and no higher than 60,000 feet of altitude. Above these limits, when the GPS is mounted to a high speed object, the GPS will not track anymore. Garmin's speed limit for active tracking is approximately 1000knots(rounded to 1151 mph), but might be slightly less, like 1050mph max. Edited November 23, 2006 by GOT GPS? Quote Link to comment
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