GPSs for cyling

Discussion in 'Road Cycling' started by hold my beer and watch this..., Nov 6, 2004.

  1. So I just moved up to the freakin' Poconos, and even though I can't seem to
    find a ride where I don't have to use my 23, its 10 degrees colder here than
    anywhere else in Pennsylvania, and I haven't seen a single another rider
    after almost a month of being here, the riding's not too bad. Anyway, I was
    thinking about getting a GPS with a bike mount to help in finding new rides,
    maybe something like this:

    http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp

    Anyone train with a GPS or have any suggestions...?
     
    Tags:


  2. packmagician

    packmagician Guest

    If you're really just looking for an excuse to buy a GPS, I guess that
    will do, but if you want to find roads, I'd suggest Microsoft Streets
    software, a printer and a plastic bag instead.
     
  3. "hold my beer and watch this..." <noone@nowhere.org> writes:

    > So I just moved up to the freakin' Poconos, and even though I can't seem to
    > find a ride where I don't have to use my 23, its 10 degrees colder here than
    > anywhere else in Pennsylvania, and I haven't seen a single another rider
    > after almost a month of being here, the riding's not too bad. Anyway, I was
    > thinking about getting a GPS with a bike mount to help in finding new rides,
    > maybe something like this:
    >
    > http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp
    >
    > Anyone train with a GPS or have any suggestions...?


    http://www.garmin.com/products/etrexVista/


    Being discounted heavily right now because they came out with
    a color version. I think I paid $210 and got free shipping (amazon).

    I didn't buy it for cycling, but brought it on a few rides. I benchmarked
    it against my Avocet and found they were within +/- 0.02 miles over a 20
    mile ride.

    I wouldn't bother with a handlebar mount, just put it in your jersey
    pocket. Works fine back there.

    There are many more disadvantages to GPS than advantages. Bulk,
    battery life, cost, etc to name a few.

    The only advantage a GPS might have over a cyclometer is the elevation
    data - for example, you can review your course profile and also it
    tells you your cumulative elevation gain during the ride.

    Overall I think a GPS is overkill. Just go wander around. More
    fun that way. The single best bike ride I ever had was once when
    I brought my bike with me on a business trip to Irvine, CA and got
    "lost" on Santiago Canyon Road.

    Poconos? Damn, better get the snow chains ready.

    -Gerard
     
  4. DirtRoadie

    DirtRoadie Guest

    "hold my beer and watch this..." <noone@nowhere.org> wrote in message news:<G7GcnUw8ROz3xhDcUSdV9g@ptd.net>...

    > ... Anyway, I was
    > thinking about getting a GPS with a bike mount to help in finding new rides,
    > maybe something like this:
    >
    > http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp
    >
    > Anyone train with a GPS or have any suggestions...?


    I use one all the time.
    There are lots of factors depending on what you would hope to actually
    do.
    Check out Topofusion.com for truly excellent mapping/training log
    software.

    Also take a look at the Garmin Foretrex. It's hard to beat for
    usefuleness unless you decide you need a "mapping" unit.
    http://www.gpsdiscount.com/products/index.html?p=804

    DR
     
  5. pedalchick

    pedalchick New Member

    Joined:
    Aug 4, 2003
    Messages:
    190
    Likes Received:
    0
    I admit it, I am a big tech geek, and I just love maps. I have this one:
    http://www.thegpsstore.com/Detail-Garmin-eTrex-Legend.asp
    and it is helpful when exploring new routes. If you have the $$, I would get one with an altimeter so you can calculate ft. of climbing done. I find it to be very reliable in calculating speed&distance - at least compared to my cyclocomputer.
    The only problem I've experienced is that the maps don't show which roads are unpaved, for how long they stay unpaved, and how many meth labs with rabid guard dogs are on them.... ahhhhh. the south.....
     
  6. Gerard Lanois wrote:
    > "hold my beer and watch this..." <noone@nowhere.org> writes:
    >
    >
    >>So I just moved up to the freakin' Poconos, and even though I can't seem to
    >>find a ride where I don't have to use my 23, its 10 degrees colder here than
    >>anywhere else in Pennsylvania, and I haven't seen a single another rider
    >>after almost a month of being here, the riding's not too bad. Anyway, I was
    >>thinking about getting a GPS with a bike mount to help in finding new rides,
    >>maybe something like this:
    >>
    >>http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp
    >>
    >>Anyone train with a GPS or have any suggestions...?

    >
    >
    > http://www.garmin.com/products/etrexVista/
    >
    >
    > Being discounted heavily right now because they came out with
    > a color version. I think I paid $210 and got free shipping (amazon).
    >
    > I didn't buy it for cycling, but brought it on a few rides. I benchmarked
    > it against my Avocet and found they were within +/- 0.02 miles over a 20
    > mile ride.
    >
    > I wouldn't bother with a handlebar mount, just put it in your jersey
    > pocket. Works fine back there.
    >
    > There are many more disadvantages to GPS than advantages. Bulk,
    > battery life, cost, etc to name a few.
    >
    > The only advantage a GPS might have over a cyclometer is the elevation
    > data - for example, you can review your course profile and also it
    > tells you your cumulative elevation gain during the ride.
    >
    > Overall I think a GPS is overkill. Just go wander around. More
    > fun that way. The single best bike ride I ever had was once when
    > I brought my bike with me on a business trip to Irvine, CA and got
    > "lost" on Santiago Canyon Road.
    >


    Definitely don't get the Magellan. I've owned a number of hand held GPS
    and Garmin is the only way to go. I currently ride with an eTrex Vista
    as well and like it a lot. It works well even in the rain. Only downside
    is a pretty big battery use, but that is true for any GPS. I would
    recommend a pair of good quality NiMH rechargables.

    The Garmin Mapping software is a good addition to have as well. I have
    MetroGuide v5.0 and it adds a LOT to the GPS particularly for cycling.

    I would definitely get the handlebar mount unlike the previous poster.
    It helps a lot, however, don't get caught staring at the damn GPS and
    ride off the road. (Try it, you'll realize I'm not kidding.)

    If you want to see examples, here are maps that I created using my GPS
    and MetroGuide v3.0 in 2001 at Texas Hellweek. Click on any article to
    see the map

    http://www.thingelstad.com/DotText/archive/2001/03.aspx
     
  7. Jamie Thingelstad schreef:

    > I would definitely get the handlebar mount unlike the previous poster.
    > It helps a lot, however, don't get caught staring at the damn GPS and
    > ride off the road. (Try it, you'll realize I'm not kidding.)
    >


    You mean there is no audio "Manolo Saiz" function, giving both riding directions
    and venga venga's ?
    Bummer.
     
  8. Gary

    Gary Guest

    I love my Garmin Legend and have the Topo USA software for downloading
    tracks into and displaying in 3-D. It's great fun! I know the purists
    say "Just get printed maps," but they have obviously never used a GPS on
    a ride. It's fun and makes me feel secure I always know where I am even
    in areas I have never visited before. And watch them get smaller and
    smaller. One day everybody will have them except the single speed guys
    who say it's just a fad like integrated shift/brake levers. LOL

    hold my beer and watch this... wrote:
    > So I just moved up to the freakin' Poconos, and even though I can't seem to
    > find a ride where I don't have to use my 23, its 10 degrees colder here than
    > anywhere else in Pennsylvania, and I haven't seen a single another rider
    > after almost a month of being here, the riding's not too bad. Anyway, I was
    > thinking about getting a GPS with a bike mount to help in finding new rides,
    > maybe something like this:
    >
    > http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp
    >
    > Anyone train with a GPS or have any suggestions...?
    >
    >
    >
    >
    >
     
  9. SpinninDave

    SpinninDave New Member

    Joined:
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    Messages:
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    0
    I use the Garmin Forerunner 201. I love it. very accurate! I can set it up to auto pause the timer when i come to a stop and it maps out the course and the elevation profile. very useful tool . well worth the 150 bucks!
     
  10. -----BEGIN PGP SIGNED MESSAGE-----

    In article <upt2q2oo6.fsf@netscape.net>,
    Gerard Lanois <gerardlanois@netscape.net> wrote:
    >"hold my beer and watch this..." <noone@nowhere.org> writes:
    >
    >> So I just moved up to the freakin' Poconos, and even though I can't seem to
    >> find a ride where I don't have to use my 23, its 10 degrees colder here than
    >> anywhere else in Pennsylvania, and I haven't seen a single another rider
    >> after almost a month of being here, the riding's not too bad. Anyway, I was
    >> thinking about getting a GPS with a bike mount to help in finding new rides,
    >> maybe something like this:
    >>
    >> http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp
    >>
    >> Anyone train with a GPS or have any suggestions...?

    >
    >http://www.garmin.com/products/etrexVista/
    >
    >
    >Being discounted heavily right now because they came out with
    >a color version. I think I paid $210 and got free shipping (amazon).
    >
    >I didn't buy it for cycling, but brought it on a few rides. I benchmarked
    >it against my Avocet and found they were within +/- 0.02 miles over a 20
    >mile ride.
    >
    >I wouldn't bother with a handlebar mount, just put it in your jersey
    >pocket. Works fine back there.
    >
    >There are many more disadvantages to GPS than advantages. Bulk,
    >battery life, cost, etc to name a few.
    >


    _ Trees and steep valleys also cause coverage loose problems.
    I tried my garmin a few times on my typical rides and it just
    loses signal too often to be a cyclocomputer replacement.

    _ Booker C. Bense

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  11. DirtRoadie

    DirtRoadie Guest

    pedalchick <pedalchick.1fcukm@no-mx.forums.cyclingforums.com> wrote in message news:<pedalchick.1fcukm@no-mx.forums.cyclingforums.com>...

    > ... If you have the $$, I
    > would get one with an altimeter so you can calculate ft. of climbing
    > done. I find it to be very reliable in calculating speed&distance - at
    > least compared to my cyclocomputer.


    Actually, they ALL have altimeters as part of the GPS function. It's
    just that most don't do anything else with that data until the
    recorded "tracks" are processed with software on a computer. That's
    where a package like TopoFusion comes in and you CAN calculate
    climbing and show graphical representations of profiles, etc., you
    just can't do it on the screen of the GPSR. While there are units
    with built-in barometric altimeters too, I believe that additional
    functionality is largely unnecessary and not worth the extra $, not to
    mention that it is another drain on the power that decreases battery
    life.

    DR
     
  12. Mark Fennell

    Mark Fennell Guest

    "hold my beer and watch this..." <noone@nowhere.org> wrote in message
    news:G7GcnUw8ROz3xhDcUSdV9g@ptd.net...
    > So I just moved up to the freakin' Poconos, and even though I can't seem

    to
    > find a ride where I don't have to use my 23, its 10 degrees colder here

    than
    > anywhere else in Pennsylvania, and I haven't seen a single another rider
    > after almost a month of being here, the riding's not too bad. Anyway, I

    was
    > thinking about getting a GPS with a bike mount to help in finding new

    rides,
    > maybe something like this:
    >
    > http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp
    >
    > Anyone train with a GPS or have any suggestions...?


    I don't train with it but I have an older version of that Magellan model and
    I like it a lot. I have also used a Garmin device in a GIS class and,
    despite what the other poster said in this thread, I cannot say one is
    better than the other. IME, they are pretty similar. If you get one and use
    it to explore new roads, perhaps its best feature is the real-time record of
    your route, which can really help you not get lost.

    Also, GPS does a terrible job of measuring altitude on its own. Barometric
    pressure is far more accurate. Perhaps I misunderstood the other poster's
    response about altitude capability, but you will see significant drift and
    variance in the altitude measurements.

    Whatever you get, please carry it in your pocket--it's too freakin geekish
    to ride around with a big dashboard like that on your bike! (Unless it's an
    SRM)

    Mark
    (Another closet map geek)
     
  13. CDR114

    CDR114 New Member

    Joined:
    Sep 5, 2004
    Messages:
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    Likes Received:
    0
    I use a Garmin Forerunner 201 with an inexpensive heart rate monitor mount, way less expensive then the Garmin mount. It is light weight and provides a lot of information but lacks mapping. I also have a cycling computer. I use both but for different reasons. The cycling computer is used for cadence, speed and total distance purposes while the Garmin is used in the "virtual partner" mode to provide a constant competitor when I ride solo. In addition, the download of data from the Garmin is great for post-ride analysis.
     
  14. DirtRoadie

    DirtRoadie Guest

    "Mark Fennell" <marco_fennelli@yahoo.com> wrote in message news:<jERjd.37445$SW3.26965@fed1read01>...

    > Also, GPS does a terrible job of measuring altitude on its own.

    Urban myth, repeated often but nonetheless not good information.

    > Barometric pressure is far more accurate.

    Only true under some very particular circumstances, but not true as a
    general statement.

    >Perhaps I misunderstood the other poster's
    > response about altitude capability, but you will see significant drift and
    > variance in the altitude measurements.


    Given a reasonable satellite fix, a GPSR is virtually always within 30
    feet or so of the correct altitude and NEVER varies as the barometer
    fluctuates. In contrast you could calibrate a barometric altimeter
    today, and tommorrow it can easily read +/-300 feet of today's
    reading at the same location. And if you have moved to a different
    location in that time you would not know you had a 300 foot error.

    So if you don't know where you are and don't know what the barometric
    trend has been, a GPSR actually gives far MORE reliable elevation
    information. On the other hand if you merely want to know the
    difference in elevation between point A and point B as you travel
    between them in some short period of time, then, YES, the barometric
    altimeter may be more accurate, especially if your concern is only the
    "relative" elevations and you don't care about the absolute elevation
    of either point.

    > Whatever you get, please carry it in your pocket--it's too freakin geekish
    > to ride around with a big dashboard like that on your bike! (Unless it's an
    > SRM)


    Depends entirely on whether you want to see any of the data or maps
    while riding.

    DR
     
  15. Mark Fennell

    Mark Fennell Guest

    "DirtRoadie" <DirtRoadie@aol.com> wrote in message
    news:c6661314.0411091215.5e723fbe@posting.google.com...
    > "Mark Fennell" <marco_fennelli@yahoo.com> wrote in message

    news:<jERjd.37445$SW3.26965@fed1read01>...
    >
    > > Also, GPS does a terrible job of measuring altitude on its own.

    > Urban myth, repeated often but nonetheless not good information.
    >


    Well, that's what I get for using a subjective term like "terrible"! Given
    that this discussion is related to bike racing, my thought is that any
    altitude-measuring device would be used in training to measure the elevation
    change of some route. E.g., I have a set of hills/mountains where I ride and
    I want to know as precisely as possible what the elevation change is so I
    can know my all-important VAM parameter :). The short hills are ~100 ft and
    the mountains are up to 4,000 ft. When I took my gps out to do this, its
    altitude measurement varied way too much to be helpful on the short hills.
    Just now, I took it outside and over a duration of a few minutes, the
    elevation varied between 74 ft and 119 ft, whereas I *know* my true
    elevation is ~90 ft. Using a barometric pressure device, I can set it when I
    start the ride, and it sure seems to be more consistent and accurate **for
    that ride**. Of course, one can always pull out a topo map and a magnifying
    glass and generally get close enough... but that's way too low tech!

    > > Barometric pressure is far more accurate.

    > Only true under some very particular circumstances, but not true as a
    > general statement.


    I still claim that pressure is better for getting elevation change, granted,
    over a reasonable time duration (as in, no storms moving in).

    > >Perhaps I misunderstood the other poster's
    > > response about altitude capability, but you will see significant drift

    and
    > > variance in the altitude measurements.

    >
    > Given a reasonable satellite fix, a GPSR is virtually always within 30
    > feet or so of the correct altitude and NEVER varies as the barometer
    > fluctuates. In contrast you could calibrate a barometric altimeter

    ....<snip>...
    > > Whatever you get, please carry it in your pocket--it's too freakin

    geekish
    > > to ride around with a big dashboard like that on your bike! (Unless it's

    an
    > > SRM)

    >
    > Depends entirely on whether you want to see any of the data or maps
    > while riding.


    That last part was a joke, but apparently not a very good one.
     
  16. gwhite

    gwhite Guest

    "hold my beer and watch this..." wrote:
    >
    > So I just moved up to the freakin' Poconos, and even though I can't seem to
    > find a ride where I don't have to use my 23, its 10 degrees colder here than
    > anywhere else in Pennsylvania, and I haven't seen a single another rider
    > after almost a month of being here, the riding's not too bad. Anyway, I was
    > thinking about getting a GPS with a bike mount to help in finding new rides,
    > maybe something like this:
    >
    > http://www.thegpsstore.com/Detail-Magellan-Sportrak-Map-GPS.asp
    >
    > Anyone train with a GPS or have any suggestions...?


    Dumbass,

    Have you considered a map?
     
  17. xzzy

    xzzy Guest

    A Garmin might be a nice "virtual partner", but I prefer the real thing and
    use a Powertap. It tells me what is happening every second . . . reminds me
    of an old girlfriend.

    John Bickmore
    www.BuyYourInkNow.com

    "CDR114" <CDR114.1ffupy@no-mx.forums.cyclingforums.com> wrote in message
    news:CDR114.1ffupy@no-mx.forums.cyclingforums.com...
    >
    > I use a Garmin Forerunner 201 with an inexpensive heart rate monitor
    > mount, way less expensive then the Garmin mount. It is light weight
    > and provides a lot of information but lacks mapping. I also have a
    > cycling computer. I use both but for different reasons. The cycling
    > computer is used for cadence, speed and total distance purposes while
    > the Garmin is used in the "virtual partner" mode to provide a constant
    > competitor when I ride solo. In addition, the download of data from
    > the Garmin is great for post-ride analysis.
    >
    >
    > --
    > CDR114
    >
     
  18. DirtRoadie

    DirtRoadie Guest

    "Mark Fennell" <marco_fennelli@yahoo.com> wrote in message news:<B8bkd.39941$SW3.34258@fed1read01>...

    > > > Also, GPS does a terrible job of measuring altitude on its own.

    >
    > > Urban myth, repeated often but nonetheless not good information.


    > Well, that's what I get for using a subjective term like "terrible"!
    > ...
    > Just now, I took it outside and over a duration of a few minutes, the
    > elevation varied between 74 ft and 119 ft, whereas I *know* my true
    > elevation is ~90 ft.


    That seems pretty accurate to me - pretty much in line with the +/- 30
    feet that I described. But I suppose what is interesting is the
    perception of accuracy. You live at about 90 feet elevation so 30 feet
    is arguably an error of about 33%. I live at 6660 feet where +/- 30
    feet seems to be an error of less than 1/2%. I note that the Avocet
    Vertechs (barometric altimeters) I have used for years tend to "lose"
    elevation when moving to higher ground. They very consistently read
    about 200 feet low when I calibrate them at home and then go quickly
    to a known elevation of about 10.5K feet. Despite the error at higher
    elevation they will read accurately upon return home. The error seems
    to increase with even greater elevations.

    > Using a barometric pressure device, I can set it when I
    > start the ride, and it sure seems to be more consistent and accurate **for
    > that ride**. Of course, one can always pull out a topo map and a magnifying
    > glass and generally get close enough... but that's way too low tech!
    >
    > > > Barometric pressure is far more accurate.

    > > Only true under some very particular circumstances, but not true as a
    > > general statement.


    See my further comments above

    > I still claim that pressure is better for getting elevation change, granted,
    > over a reasonable time duration (as in, no storms moving in).

    And I agree under some circumstances. Asuming that the instrument has
    sufficient resolution (my Vertechs have all had a measuring resolution
    of only 10 feet -newer ones are 5 feet), the accuracy improves with
    smaller elevation changes over smaller periods of time, with smaller
    changes in location. The accuracy or inaccuracy of GPSR is fairly
    consistent, dependent only upon its "view" of the sky. Most GPSR's
    have a screen to indicate how well it can see the satellites at any
    given time so that is not an unknown variable.

    > > > Whatever you get, please carry it in your pocket--it's too freakin geekish
    > > > geekish to ride around with a big dashboard like that on your bike! > > > > > > (Unless it's an SRM)

    > >
    > > Depends entirely on whether you want to see any of the data or maps
    > > while riding.

    >
    > That last part was a joke, but apparently not a very good one.


    I admit to having hidden a GPSR in a water bottle just to avoid the
    geek factor, but that does inhibit its use for actual navigation.

    DR
     
  19. >>Also, GPS does a terrible job of measuring altitude on its own.
    > Urban myth, repeated often but nonetheless not good information.


    Read this as it will provide the mathematical and geographical
    theory why GPS altitudes are not accurate.

    http://www.esri.com/news/arcuser/0703/geoid1of3.html

    I do admit though that for cycling, who cares if it is off by
    100 feet from the mean sea level. For the most part we only
    care about vertical climbed. For these purposes, the GPS is
    probably more than what we need as we don't really care if we
    are off by 5% vertical.

    Having said that, the FAA just approved VNAV (vertical
    navigation) approaches for aircraft based on GPS with WASS.
    Now keep in mind that
    the requirement this type of approach requires the GPS has
    a barometric input into the GPS and the GPS will determine
    if the accuracy for the approach has been met (RAIM). Blabbering
    more, precision approaches (VNAV and ILS) can have as little
    as 50 feet clearance from the highest structure on the approach
    path (inside the inner marker) so an accurate altitude is quite
    important when you break out of the clouds at 200 feet above the
    ground and moving at 140 mph. Ok, more detail than you wanted to know.....

    >>Barometric pressure is far more accurate.


    yes but does need to have the local barometric pressure setting.
    But in a local environment it is more accurate. If you go out
    on a 50 or 100 mile ride straight out, it will be less accurate
    as the local pressures do change and are different.

    > So if you don't know where you are and don't know what the barometric
    > trend has been, a GPSR actually gives far MORE reliable elevation
    > information.


    possibly. If you know the phone number of a local airport with
    a ATIS/AWOS you can easily get it though (see AIRNAV.COM). Or you can
    just log on to say WUNDERGROUND.COM and get it that way.

    For flying, I'll take a Garmin 430 or 530. For riding, I'll
    just base it on what others have measured and posted on the internet.
    If I can't find it, it probably isn't a big enough climb anyways.

    Gerald Sylvester
     
  20. DirtRoadie

    DirtRoadie Guest

    Gerald Sylvester <sylveste@earthlink.net> wrote in message news:<43kmd.21900$6q2.21555@newssvr14.news.prodigy.com>...
    > >>Also, GPS does a terrible job of measuring altitude on its own.

    > > Urban myth, repeated often but nonetheless not good information.

    >
    > Read this as it will provide the mathematical and geographical
    > theory why GPS altitudes are not accurate.
    >
    > http://www.esri.com/news/arcuser/0703/geoid1of3.html
    >
    > I do admit though that for cycling, who cares if it is off by
    > 100 feet from the mean sea level.


    That article is interesting but is focused on why the MODEL used for
    GPS elevation is inaccurate not on the accuracy (or consistency) is
    the instruments themselves. The "urban myth" I was referring to stems
    from the oft repeated claim that because of geometric constraints, GPS
    is more accurate horizontally than vertically. This assertion is then
    commonly extrapolated into a claim that, therefore, GPS is not-at-all
    accurate vertically.

    Even the cited article refers to variations of "a few meters" citing
    an extreme exapmale of 32 meters at one location. Of course even that
    is not an outrageous error. In my experience GPS elevation seems to be
    very accurate (+/- 30 feet), especially when viewed over time and
    averaged at a specific location (typically +/- 5 feet) or when a
    viewed continuously such as in looking at the elevation profile
    created from a "track log" of a ride (see Topofusion.com) Such
    profiles are surprisingly smooth even when trackpoints are recorded at
    high resolution such as every 1 or 2 seconds.

    If the global elevation model were actually far off then the measured
    elevation would always tend toward an inaccurate reading, which it
    does not. (And, of course, when I refer to "accuracy" I am comparing
    to measurements assumed to be good, such as USGS topo maps)

    > >>Barometric pressure is far more accurate.

    >
    > yes but does need to have the local barometric pressure setting.
    > But in a local environment it is more accurate. If you go out
    > on a 50 or 100 mile ride straight out, it will be less accurate
    > as the local pressures do change and are different.
    >
    > > So if you don't know where you are and don't know what the barometric
    > > trend has been, a GPSR actually gives far MORE reliable elevation
    > > information.

    >
    > possibly. If you know the phone number of a local airport with
    > a ATIS/AWOS you can easily get it though (see AIRNAV.COM). Or you can
    > just log on to say WUNDERGROUND.COM and get it that way.


    I find this comment to be very funny if only for pointing out the
    difference in perspectives from which we view this. I use GPS most
    commonly for biking and hiking in mountainous areas where there are no
    local airports and one does not generally have the option of simply
    logging on to WUNDERGROUND.COM to get barometric figures. For that
    matter, even assuming the existence of a suitably close airport, due
    to the varying terrain it is very common for even a cell phone to be
    out of service range or simply blocked (no I can't "hear you now").
    But even under such circumstances a GPSR will provide a
    more-than-acceptably accurate elevation reading without all that extra
    rigmarole.
    >
    > For flying, I'll take a Garmin 430 or 530. For riding, I'll
    > just base it on what others have measured and posted on the internet.
    > If I can't find it, it probably isn't a big enough climb anyways.


    Flying - now that's a whole different ball game and "accuracy" can
    take on a whole new, perhaps life-or-death, significance.

    DR
     
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