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Posts posted by stevesisti

  1. What's with the SirfStar III chipset that is offered in the new x line of Garmin GPSr's.


    Does this only effect processor speed or does it have anything to do with the units ability to get a signal, especially in dense tree cover?

    It would be hard to surmise what the sirf lll chip will mean in actual performance in a handheld unit until the first units are out. My crude understanding is that the "advantage" is due to signal processing by the chip and not by improved antenna design. On a common sence level, for garmin to sign a "major" contract with them for chip supply, Sirf must have something of value in their technology.


    I have only seen or read about "external" units incorporating the technology to date..the reviews seem good...my only question is if the increased sensitivity can be maintained in "handheld" units, using the same antennas as they exist now. Time and user reviews will tell.

  2. My bet is that you need to change the "datum" in your SportTrack to WSG 84. If it is set to NAD 27, you're likely to be a couple of hundred meters off. Also, although it sounds like you have it right, be sure that your coordinates are set to hdd° mm.mmm (hemisphere degrees, minutes.decimal minutes).


    Benchmarks that are listed as "scaled" are not too accurate (someone guessed their coordinates from a map). If the benchmark is "adjusted" its coordinates should be dead on.

    Hmmm, a couple hunderd meters off because of the NAD27 vs WGS84 seems like way too much. Have a look here a chart Peter Dana produced to get a rough idea of what the difference would be.



  3. Hi all.


    I have City Select v6 and a one GPS 60c. I used one unlock under v6. I have the update DVD for v7. If I unlock the update DVD to my one GPS will I lose the ability to use the second unlock if I ever get another GPS and need it?


    I hope this doesn't sound confusing. I checked Garmin's site and it appears that I will lose the second unlock but then I read something else and I'm not so sure.


    Any help will be appreciated. Thanks.

    The unlock is for a particular unit, and a particular product...... not a particular version. If you update to v7, you still will have one unlock code left for another unit.

  4. I have no idea what is "advertised" - what I reported on are my observations based on using the altitude readings of my GPS receivers on an almost daily basis over the last 6 years and comparing them to known values where that was possible

    I wasn't referring to your comment regarding quoted accuracies, but rather the original poster...... If I was referring to your comment, I would have replied to your post.


    Also note that my comment regarding possible different accuracies was not referring to the GPS derived altitude...but rather the Pressure sensor contribution to the final altitude. All sensors, pressure, temp etc...do not respond in a straight linear fashion...especially not near the top or bottom of their recommended range....not only is it likely, but it's extremely probable that the Pressure sensor is more accurate in the middle of it's intended range and not near the top or bottom.


    Lastly...If one has to , as you say, start discerning whether or not they have a "good lock" a "not so good lock", or a "bad lock" , and\or factor in geoid elipsoid tables for the particular area they are in to get accurate results,Geeeez..... why bother with the thing in the first place. Bottom line is the altimeter is a rough estimate of what your altitude is......being off by 25-30% is "rough" to me........to you it might be hair splitting accuracy. :blink:

  5. I don't see anywhere near those accuracies....I spent a fair amount of time using the altimeter, and checking it with the GPS derived altitude....seems theres always a fairly big difference.


    When used in autocalibrate mode, the altimeter relies on the GPS altitude to correct it. Keeping that in mind, it's not unusual for me to get GPS derived altitudes that vary by 50 ft on a 200 ft altitude. And I'm not talking about a 1/2 hour time gap between readings....I'm talking about 10 sec. This is also not in a "slot canyon" I was in, or deep in a ravine...this is on top of a mountain under heavy tree foliage. I've done it several times and had the same result.


    Maybe the figures you quoted are what they advertise, but I highly doubt you will see that accuracy.


    Maybe more important is do you really need that much accuracy in an altitude measurement. I was initially annoyed because the readings seemed to fall far short of what was published, but after thinking about it, just how accurate a reading do you really need. Personally I find the contour lines on my "homebrew" topo to be more accurate without the calibration fuss. My experience has been at "relatively" low altitudes, and it's entirely possible the units are more accurate (% wise) at higher elevations.

  6. Very Possible and fairly simple...you might need to purchase one software product like Oxiexplorer, in a nutshell...


    Find a local source who does flatbed scanning to the size of your maps. If the maps are too big you can scan just the section with the "trail" you are interested in, making sure you have at leat three intersecting grid marks with a known Lt \Lon. 300 DPI resolution should be sufficient.


    Once the map is scanned you have a digitized map image which is not georeferenced. Using Oziexplorer, you can import the digital map, find and mark the three calibration points entering the lat lon at the intersections, and Ozi will calibrate the map. From there, again in Oxi (or other software), you can manually click along the trail to create any number of track points you want. Then you save the track and you have a permanent record of the trail. Ozi tracks are PLT files but any one of a number of free software products can convert the track to other formats if necessary. I'm using the demo version, it's even possible the full version can do this conversion..you have to check.


    From here you can use any map program like delorme or national geo and import, display and print your tracks (trails) on std USGS DRG or other map of your choice.


    You could use the free drg map sources on the web, but then you get into a problem with trying to organize and manage the various map names and quads.....much simpler to decide on a good mapping program that would cover all the areas you are interested in, buy it, and use that as the source on which you lay the trails you have created. Odds are the original maps you were using were in fact USGS DRG 1:24K maps. National Geo State topo series would be the same, with some minor trail and update info added.

  7. Well I don't know why I never saw this, but Map Edit will driectly open a Grmin GDB file....so just load your GDB track into Map Edit, whether you derive the track with your GPS or trace/create the track in another program.


    Sorry, got off topic a little bit.....as far as your concerns go, there should be no problem with you altering the map and using it yourself, The "new" work you created is your property, having already paid the license fee to Garmin for the topo version of their software. If your "friend" has topo, he too has a license to use it, and their should be no problem with him using "your" created work. If your friend does not have a legit copy of Topo, and you're going to give it to him to upload thru 3rd party software, that's definitely a copyright violation.


    In the 'real world", no one gets chased for giving something to a friend. Mass distributing for free or for a price would definitely get someone knocking on your door.

  8. "copy it and paste it into the topo section in question. Then I would have to reprocess the section with cGPSmapper"


    CenTexDodger... I'm always interested in tweaking the maps. Do you have some details on how you pasted into the topo file, and the steps to reprocess in cGPSMapper?


    stevesisti... you're holding out on me! :rolleyes: ...neat utility for converting tracks!



    Sorry JJ, just fond it this morning....as I said, haven't even had a chance to try it yet. Thanks for the advice on the "overlay"....It's best to "check the Box" before saving and converting to .img.


    By the way, I seemed to have lost the .mp file version to a rather large map section I made...have you tried converting from a .img file back to a .mp file. I thought cgpsmapper.exe would do that but I'm having no luck.

  9. How do you do a transparent overlay? I tried an overlay and it blocked the other map features.


    Alright. I figured out which MapSource Topo Section my dad's ranch was in. Then I used GPSmapEdit and USAPhotomaps to draw a vector map of my dad's ranch.


    Then, hypothetically speaking, I would take the drawing of the ranch copy it and paste it into the topo section in question. Then I would have to reprocess the section with cGPSmapper. Then (again hypothetically) I would rename the section and transfer it into the folder that contains the topo maps (having first put a copy of the original section in a folder by itself.


    Anyway, It might look really cool to see the ranch boundaries and inside fences on my GPS.


    Also, help with transparent overlays would be appreciated!

    In Mapedit there is a checkbox to make the map transparent. You must be careful that it is checked when you save the map, as for unknown reasons, working on the map can sometimes "uncheck" the box. I have created a 63 Sq. mi overlay of topo contours, streams and lakes. The map "overlays" the City Select 7 maps, and you can see both at the same time. One click on the "custom map" removes all the topo and water data. All the topo, lake, stream data uses 250K for 63 Sq. mi. I wouldn't want to do this for the whole country, but this is a state park I spen a lot of time doing photography in. The complete overlay took 3 hrs to make.


    Seems like an awful lot of work just to get an outline of the property....I haven't tried this yet, but it is a program to convert Garmin tracks to a Shapefile. All my maps have been done by "importing" shapefiles into Map Edit. New York State (where I live has the Dem (topo) data, Hydrodata, (Lakes and Stream)) available for free download.....I use Global mapper to import the data, convert it to Lat\Lon WGS84 data and the export from Global Mapper the shapefiles I need. Then it's a simple matter of using Map Edit to import the shapefiles, which once in Map Edit can de "edited" to suit your taste.


    In your case, walk the property kine, save the track, try out the link listed to convert track to a shapefile, and then import the shapefile into Map Edit. Try the track converter site first, unless you don't mind going for a walk :rolleyes:


    Link to converter.... http://www.digitalgrove.net/Toolbox_GPS.htm#waypt+


    Good Luck

  10. Hello folks...


    I have some very detailed hiking maps from a couple of outing clubs that show trails on them. I want to have access to those trail maps on both my PDA and my GPS. I have not found any track/route data sites with these particular trails so far and I am beginning to think that I will need to scan them and do the conversion project myself. Hope I haven't bitten off more than I can chew!


    What software do I need to scan those maps, calibrate them and them upload them to a GPS?


    I have ordered Rich Owings' book GPS Mapping but I wanted to get a jump on looking at the software while I was waiting for the book to come in.


    I will be interfacing with a Garmin GPSMAP 76cs and have Garmin Topo and Delorme Topo already here.



    It depends on how involved you want to get...I have made an overlay for use on my 60CS. It's transparent, details rivers, streams, lakes and topo, and it overlays city select7 maps. Thats fairly easy because all the overlay info is already vectorized and available from the NY State GIS clearinghouse. Using some of the programs mentioned in Rich's book, it's fairly simple to make a nice custom map. The overlay I made covers 63 SQ mi., and only uses 146K of map memory to enable me to get both street detail and topo detail.


    If it's the trails you're interested in, the simplest thing to do would be to ask the outing club how they arrived at the trail data...if they arrived at it from a GPS track, it's easiest to ask if they would mind giving you the track info, and just incorporate that into the std. garmin product as a track.


    If that info is not available your only choice is to scan and calibrate the map using any one of a number of different programs. Once you have a calibrated map you can simply just trace the track with a program like Oziexplorer (or others) and convert into a Garmin compatible track that you can load to the GPS. You can go further and make your own map from scratch, incorporating and making the track an integral part of the map....you should be advised that you'd better like this mapping stuff because it certainly takes a lot of time to make one from scratch.There is a lot of "free" data floating around in the GIS world, but you need to be aware of all the different datum and projections...it's easy to think you have incoroprated data into your mapset, only to find it's geographically out of position.


    I suspect rich's book would make things easier than the "trial and error" path I have gone down, but experimenting with different map data sets helps you get a feel for what you want to include in your map.


    As far as getting a jump on things...I would just wait for the book, theres an awful lot you must familiarize yourself with before making the map.


    Best of Luck

  11. Again, he and others miss the point. I won't restate it.


    Is the world so BORING now that people have to take a simple reply and turn it into a life and death struggle? For god's sake, get a grip.


    Its simple: if you want screen protection, BUY IT. It may not be a waste of money for *you*. It would be a big waste of time, effort and money for *me*. :: Expecting some worthless response from BubbleBoy ::


    Beffiness, enjoy your new GPS and have fun buying things for it.




    See....now you've got it. Cut out all the stuff you're just making up and you only needed one sentence to reply in the first place. Quite an improvement !

  12. I wrote the following message to Garmin Tech Support (I was not sure where to send it, so I sent it to them):


    Dear Sir,


    I am a current user of a Garmin GPSmap60cs. I use City Select V6, along with Topo USA and these software products work very well in my unit. I was disappointed to learn that City Select will no longer be produced after V7.

    I underdstand that the map data in City Navigator is virtually identical to the map data in City Select; however, the large map segments in City Navigator will make it difficult for users of fixed memory handhelds (such as the 60cs) to build a custom map upload to suit their individual needs.

    Such large map segments will force users to load large areas they do not need at the expense of areas they do need. Please consider us fixed memory handheld users as you design V8 of City Navigator. Perhaps you can produce a small segment version for handheld users and a large segment version for fixed mount, large capacity users. Also, please consider allowing current City Select users to upgrade to City Navigator for the upgrade cost, rather than requiring us to pay full price for the new software.


    I sincerely believe that you have your users and customers best interests at heart, and I am confident that you will consider how your products are used as you implement upgrades in the future.


    Thank you for your attention to this matter, and thank you for producing the high quality products that I have come to depend on. There are many loyal Garmin users/cheerleaders in the handheld GPS community, and I am confident that you can produce products that we can continue to rely on and cheer about.






    I received the following response:


    Thank you for contacting Garmin,


    I've posted your letter to our suggestions box, and I really believe they'll address many of your (and my) concerns in the next release of software. 


    Best regards,


    Carl Huffman

    Product Support Specialist

    Garmin International

    1200 E. 151st Street

    Olathe, KS 66062

    Ph. 1-800-800-1020

    Fax 1-913-440-5488


    Maybe they are starting to hear us out there.

    Seems like a reasonable response....I really would be shocked if they didn't address this, as it would be "sucidal" to leave 24 meg units unable to load certain map sets. I would guess they already have..they just haven't released the details.

  13. I had already scratched my screen before I put on the "invisible shield".......there is no change in light level at all..I still use the same setting at night I always used.....the few scratches I had have all but disappeared or at least no longer cast a distracting "shadow" on a sunlit screen, which was a pleasant surprise.


    Moreover, I find the protected screen tends to not show finger smudges as much as the unprotected screen.  Usually I would say products like this are all hype and no substance, but that's not the case here.  This is an excellent way to protect from scratches, and diminish the ones you already have.


    As far as all these light reduction calculations go...geeesh...you're reading way to much into a piece of protective plastic.  All sorts or products(eyeglasses, car winshields, CRT screens, LCD's etc.) have a layer of protective plastic over them.  If light reduction from a 1 mil piece of plastic was as you say, there would be a lot of people walking and driving into things because they can't see. :D

    You missed the point *completely.*

    Well I don't think so..as a matter of fact , for a physicist, you really have no idea what you are talking about.


    First of all you state most people can see a 2.5% difference in luminance...you're off by a factor of ten....it's common knowledge in many scientific circles that the majority of people can't even distinguish a 25% difference in a given luminance value. I attribute that error to pure BS on your part.


    Second of all, the adhesives used to affix protective polymer sheets have a light transmittance value which is equal to or greater than the light transmittance value of the plastic it's being used on. For a supposed physicist, you don't even understand the most rudimentsry principles regarding light. Equal Transmittance values equal no loss of light. It's also entirely possible, and probable, that the screen protector plastic has a higher transmittance value than the plastic screen on the unit.


    Thirdly, obviously you have never used "invisibleshield" because the screens use "water soluable" adhesive...Don't know how you got alcohol on your brain (well maybe I do :P ), but peeling off and wiping with a damp cloth is all thats needed to remove them.


    Also don't know where you got the exacto knife thing from....maybe you're a real hack and like to cut everthing you get your hands on, but it's not necessary with this protector...it's already cut to size and fits perfect...so put your exacto knife away, and get away from the GPS.


    Lastly, most people that need to boast about their earnings to support what they say are usually full of &*(%. Mike Tyson made a lot of money but he's far from the sharpest tool in the shed. Get my drift :P

  14. That's cool.  Everybody has their own likes and dislikes.  I just disagree with your disagreement.  :D


    However, given the amount of screen cratches I've accumulated on every cellphone I've ever owned, as well as my Rino 110* (replaced), Rino 130* (replaced), and 60CS, a screen protector is a cheap AND worthwhile investment. 


    Invisible Shields are just that - transparent.  I used PDA protectors cut down on my GPS units, but they do offer a bit of glare - it's there, but tolorable.  I don't see that on my 7520 Blackberry now.  It disappears.


    For the investment - $4 for a pack of PDA protectors, $8 for an invisbileshield, which has a lifetime warranty -  it's an easy decision to make.  As for "changing the design of the unit" - they don't.  One of the Garmin techs I spoke to (while having Rino 130 issues) actually recommened them.  He said "They're cheap, and it doesn't affect the reception."


    Yeah, it could be said that I'm "hard" on my units - they hang on my belt clip (as does my phone) a lot of the times, and I do tend to bushwack.  The Rinos - even with their Bash Guards, still get plenty of unwanted "action."  But then, I bought 'em to be rugged.  The 60CS, not so much, but it goes with me on out of town trips instead of saying in the truck.  And it's a fairly rugged unit.


    * - The Rinos were each individually replaced under warranty at different times for different issues, NOT for "screen scratches".  The 110 took a 10 minute swim 20ft down in a lake, and the 130 had severe microphone issues.  Unfortunately, the 60CS is working flawlessly so I have to live with the small scratch in the middle of the screen.

    You don't disagree with me. 1) You agree totally, 2) you confuse "transparent" with "transmits light 100%," and 3) you misunderstand "design change."


    Part 1: You are (self-admitedly) rough on your unit(s). Re-read my comment. "Unless you are rough on your unit ..."


    Part 2: These screen covers absorb a certain percentage of light from the display. Imagine it this way. Ask yourself "How many of these covers can I add, one on top of the other, before the light from my unit is reduced to half? Now, guess. Lets say they are well made and fairly transparent. Lets then say that it takes 25 layers to reduce the outgoing light to 50%. That is a little more than 2.5% (2.734) reduction in light. When you choose the lighted setting, with 2.5% reduction easily within human perception, you would (at some rate) choose to view the screen at a higher brightness. Brighter screen = more power comsumption = shorter battery life.


    Realize this: the screen itself may be very transparent (99%). How transparent is the glue used to attach the Invisible Shield to your screen? I think we just found out!


    Part 3: I said that you are changing the design of the unit, by adding a part (the InvisibleShield) that the unit was designed without. As to your comment that "they" don't change the design of their (Garmin) products: I own an eTrex Vista C, "C" being the operative part of the statement. Before the eTrex Vista C was the eTrex Vista. How do you spell "D-E-S-I-G-N C-H-A-N-G-E???"


    Now. Are you rough on your stuff? Are you so rough that you need a neoprene case and "transparent" view screen? Do you *want* to pay high prices for how many lifetime guaranteed screens? Buy them. *Stick* them on your beautiful 60 CS. Fog your screen with the alcohol you use to take the old glue off when you replace the Invisible Shield. While you are doing all that, I'll be enjoying by GPSs, not damaging my screen with the Exacto-Knife when trimming the protector, taking care of my stuff (I wash mine daily), and spending the saved money on a new GPS when I want one.


    Different strokes for different folks. I believe this is *enough* said on this topic. :P



    Radiation Physicist

    (I know these things. That's why I make the big bucks!)

    I had already scratched my screen before I put on the "invisible shield".......there is no change in light level at all..I still use the same setting at night I always used.....the few scratches I had have all but disappeared or at least no longer cast a distracting "shadow" on a sunlit screen, which was a pleasant surprise.


    Moreover, I find the protected screen tends to not show finger smudges as much as the unprotected screen. Usually I would say products like this are all hype and no substance, but that's not the case here. This is an excellent way to protect from scratches, and diminish the ones you already have.


    As far as all these light reduction calculations go...geeesh...you're reading way to much into a piece of protective plastic. All sorts or products(eyeglasses, car winshields, CRT screens, LCD's etc.) have a layer of protective plastic over them. If light reduction from a 1 mil piece of plastic was as you say, there would be a lot of people walking and driving into things because they can't see. :P

  15. - 50 reversible routes

    - 10,000 point automatic track log

    - 20 saved tracks (500 points each)


    Ok so this is what the specs are on the gps that I want to buy. what I am concerned about is just how far I can go on this capacity. How often does a track point get logged?

    500 log points doesn't sound like much.


    What I am doing is trail riding with my quad and want to log all the trails that I go on. Some of my rides are like 40-50 miles. I need somone who has done this to put these numbers in to perspective. The Magellan Explorist has unlimited track point via their SD card but the Garmin is fixed.


    thanks in advance


    (lost in the forest with a gps with dead batteries)

    I believe the smallest distance setting for track recording on the 60CS is .01 mi, or 53 ft. So..... a 50 mi trip with a track pt. every 50 ft (most detailed) would use just about half your available "active" track points. Of course if you recorded a track point every 100 ft, you could double your travel distance.

  16. The satellites are of course owned and operated by the military so it free to use them or like gamps said we pay for them on April 15. You mentioned the rhino so perhaps you are talking about license and fees to use the two way radio features of those units. The rhinos will transmit on FRS frequency's and GMRS frequencies. The FRS part does not require a license but the GMRS defiantly does.


    stevesisti types faster than me so he beat me to it. I think the fee is about $90 though.

    I type faster but don't always have accurate info...the fee is listed as $80 on the gov't website :anitongue:

  17. Does anyone know if there is a GPS use license fee imbedded in the cost of each GPS unit, and if so how much per unit? I recently had someone tell me that there was .... and frankly it has never come up on the forum. I had to get a FCC restricted radio operators license in the early days of my flight training, and wonder just how the GPS Rhino units handle radio communication fees as well.


    :anitongue: ImpalaBob

    There is no built in fee on the Rhino...On the radio side of the unit, just using the FRS frquencies does not require a radio license. If you use the GMRS frequencies, then you are required to get a licence. I think the fee is $35 and there is an online site where you can apply. In reality, the vast majority of people I run into are using the GMRS freq. without a license......which doesn't make it right, but that just appears to be the way it is.

  18. :rolleyes: Alphawolf, I find it remarkable that you continue to talk on this subject when according to your profile you have never found even 1 geocache! Selling items and putting on clinics about them is not the same as using them in the field under actual geocaching conditions ie: finding 20-30 caches in a 20-30 mile radius in one day. I don't which to flame you though I may already have and if so I apologize.

    All you retired spies are alike....looking deeply into someones background before making a comment.....what happened to the archeological side of your bio...I'm sure theres a much "nicer" person lurking there. :P

  19. Well I don't think so....


    When I am "bushwacking" that is, traveling cross country, off trail, I use my GPS and compass to navigate. I have my map with me of course, but it is only to "check" my progress. I never leave my GPS turned on, so as to save battery life. A usual scenario would be as follows (In fact this is the very way I use my GPS 98% of the time):

    I have previously entered a waypoint and I am now moving towards that waypoint. It might be my camp or my truck or whatever. I turn on my GPS, wait until I have satellite lock up and do a "GOTO" for the waypoint. On my compass page (Of course it isn't really a "compass"), I don't even pay attention to the bearing arrow or the heading directions around it. I simply look at the distance and bearing windows. I am always standing still when I do this. I'm not moving at all. Now, say it says my truck is 6.2 miles at bearing 270(mag.) , I simply turn my GPS back off to save batteries and put it away. I then pull out my compass, sight a bearing of 270 and walk towards the most distant thing I can see along that bearing line. I will occasionally redo this drill on my way to my truck, especially if I have had to detour around an obstacle, checking distance, bearing and re-shooting with my compass. It works perfectly standing still, and I haven't missed (AKA: gottten lost) yet!

    Sure that will work....once you have established a waypoint you can certainly get a bearing to it. If you haven't established a waypoint and or change your destination or route, well i guess thats a different matter. I always have been curious....how well does the Fortrex keep lock under heavy tree cover...is it intermittent if you leave the unit always on.

  20. The units without an electronic compass will only give you a real compass reading if you are moving over a certain speed.


    Hmmm....If my Foretrex is reading in "degrees" instead of "cardinal letters" for my bearing , and my gps is set to magnetic north instead of true north, then all I have to do is shoot a bearing with my $8.00 Silva compass a follow it. Even if I am sitting still.

    Well I don't think so....If you are walking and get a reading, say 90 Degrees, and then you stop moving, and the reading stays the same, yes you are correct. With my GPS compass off, the the screen will rotate trying to maintain track up orientation....obviously since the compass is turned off, the units attempt to reorientate the page track up is based on new GPS readings which are indicating a "different" bearing direction than before I stopped. I believe this is caused by the basic accuracy of the unit, as while you are standing still it is laying new "points" within its accuracy circle which could be infront of, behind, or to the left or right of your current position. I think for any gps you really have to be moving for a GPS derived direction indicaton to be accurate. And that's not really such a big deal...just look at the bearing before you stop, stay facing the same direction and use your Silva.


    If used with a map, you could use your method with either true or magnetic, the latter requiring a declination for your area depending on the map.


    I frequently lay my gps on top of my topo paper map and the only way to orientate them in the same direction without the page "turning" is to use the compass to settle the movement and hit the rocker key to lock it in place.

  21. While I think the altimiter is more "show" than function...

    The altimeter is a very functional instrument. It is there to provide elevation data when you can't get a good lock on the sats, and knowledge of your altitude is critical. That scenario can play out frequently when mountain climbing (think search and rescue).

    Well that is what I thought, and maybe I don't have a representative unit, but consider the following.


    You can only calibrate it accurately at a "known" elevation, or a known pressure. For average useage your pretty much limited to a known elevation.


    You say it comes in handy when you "don't" have good satellite lock, but the autocal feature relies on the GPS computed altitude to "correct" or autocalibrate the nuit. Bad sat geometry or bad reception gives you a faulty calibration. I find using a topo map and contour lines are much more accurate than the altimiter....I rarely get agreement between a topo map and the altimeter....in an area I frequently travel, the altimiter is typically 40 ft off on a 160ft elevation. While the readings start out fairly accurate, in autocal mode it doesn't take long to have a drift to inaccuracy. I'm not expecting perfect accuracy for the altimiter to be useful, but being off 25% seems a lot. Granted these are not "high" elevations and perhaps the resolution of the pressure sensor has greater sensitivity at higher altitudes.


    I'd be curious to hear what you are typically experiencing as a differential between actual and displayed altitude. When your sat geometry is not the best, do you experience greater errors.


    In the absence of topo derived elevation data, it's certainly better than nothing, but then too I would be more likely to transfer my position to the paper topo map I carry and trust that inference.


    Could also be I have an atypical unit, with most other people experiencing better accuracy than I am. (the unit is a 60 CS)

  22. Just how good are the compass and altimeter features that Garmin includes on the "S" models?


    I know that the S stands for "compass, altimeter, glide ratio and vertical speed to destination calculators" but I really want to know if they add much more functionalisty than the units without them.


    Do they maintain calibration?

    Do they lose position and have to be reset during a hike or trip?

    If you do a reset, what does that do to the data you might have collected so far on a trek?



    While I think the altimiter is more "show" than function, I wouldn't want to be without the compass. I always use "trackup" when navigating. If you stop walking for just a moment, the next few trackpoints will invariably turn your GPS map so that it is no longer 'Track up". When I want to orient myself to the landscape or to a paper topo map, I turn the compass on, get a bearing, and touch the rocker button to "lock" the map view in the current orientation. Now the GPS map is oriented to the way your facing, and it's easy to use in conjunction with a topo map. You could also put the map flat on the ground and do the above to align your paper map with your gps map. As nice as the the 60cs "map view" is, it doesn't quite compare to viewing a 1:24K topo map in getting an overview of the surrounding terrain.


    Considering the weight of a topo map and hand compass, I don't know why anyone wouldn't carry them as a back-up. Having said that, I find the operation much more simple to use the GPS for compass readings.


    It takes about 30 sec to calibrate the compass and recalibration has no effect on already stored track/distance info.

  23. I think you're missing the whole question...and point.  The original poster asked how to project a waypoint on a 60 CS....that involves uses the on board compass, you know, the one you want 3 decimal places in.  No matter what you do with the 60CS, its accuracy is plus or minus 5 degrees....period.

    The OP poster said nothing about internal compasses. And waypoint projection doesn't depend on magnetic compasses anyway.


    Just because the internal compass in the 60CS sucks doesn't mean that it can't project waypoints accurately.


    A waypoint projection involves projecting a geodesic a specified distance in a specified direction. Accurate projections are usually done using azimuths from true north, not magnetic north. Surveyors do projections accurate to less than an inch over distances of several miles.


    Claiming that it's useless to do accurate projections because the internal compass of the GPS is inaccurate is more or less equivalent to saying that quarters and nickels are the same size because your ruler is so bad. It just doesn't make any sense.

    I don't think the internal compass on the 60 CS sucks.....for what it's supposed to do I think it works just fine. My point was that it's useless to use the compass projection to degrees three decimal places considering the compass accuracy. And the way the unit is set-up, it's obvious Garmin chose the accuracy units they did because they intended the primary use to be with the "sight and go" function of the unit.


    In fact for general navigation, the unit with it's native resolution and accuracies is just fine.


    Where would you need three decimal place precision.....well in the example given it's a heading to a cache........With most handheld units out there not being able to project to three decimal places, why do you think the cache creator used three decimal places? He used three decimal places to make the cache more challenging, knowing that to find the cache you have to put in a little more effort and go through a second step. He didn't expect you to cry and complain about not having three decimal places in your handheld....he expected you to be resourceful and find an alternative way of arriving at the cache without just entering the info into your GPS.


    And if it wasn't the projection degrees, the hider would once again find something else to add to the degree of challenge, forcing you to use sources which are not just available in your handheld. That's supposed to be the fun of it.

  24. The purpose of projecting a way point is to use the onboard compass.

    I beg your pardonWhat?


    I can use a compass, onboard or not, just fine without projecting a waypoint. The purpose of projecting a waypoint is to calculate a new waypoint. Read the rant section of my post again. Suppose I am required to project a waypoint five miles from a starting position and am given a bearing of 42.758°. If I'm limited to whole degrees, the resulting waypoint is more than a hundred feet from the intended location. More than twice that if the given bearing is 42.5°. Double the error again for a ten mile projection.


    Actually, I know a cheat I could use to get close to the required accuracy using only whole degrees. But that's for another thread.

    I think you're missing the whole question...and point. The original poster asked how to project a waypoint on a 60 CS....that involves uses the on board compass, you know, the one you want 3 decimal places in. No matter what you do with the 60CS, its accuracy is plus or minus 5 degrees....period. Adding more decimal places does nothing to change that accuracy.


    Use a little common sense......The "project a waypoint" function was designed to be used in cunjunction with the "sight and Go" feature. Having no decimal places is consistant with the accuracy of the compass itself and the accuracy of ones ability to sight with the case markings provided.


    If you have some wierd requirement to project a waypoint to 3 decimal places over 5 mi., use one of the on-line programs to get your waaypoint and then punch in the calculated data. 99.999% of 60CS users could never dream of using 3 decimal places in practical usage.


    Lastly, large style type for dramatically emphasizing your point went out of style 5 yrs ago.....unless you have an inferiority complex, std. size type is just fine for getting your point across.

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