SiliconFiend
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Posts posted by SiliconFiend
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Yet again, this isn't an issue. This is even covered in the (GPSmap 60 units) users manual.
When any GPS hasn't established a satellite lock, not only does it not know where it is, it doesn't know when it is. When the unit is moved a considerable distance and has been turned off for some length of time (not sure how long this needs to be), the GPS isn't aware of the positions of the satellite relative to its position. This is especially true when batteries were removed or discharged.
You guys know this. If not, where have you been? Especially if you own a GPSmap 60 unit. This is a common situation with that device. You expected something different with this unit?
I am not a GPS pro, but I have taken considerable time to read about and use all my GPS units. I have more than a basic understanding of its operation. It seems that there are two camps here: Those with this information (who don't have major issues with the Colorado) and those without this information (who have major issues with the Colorado.) Also, I rarely read that these folks with issues have actually called Garmin and discussed these issues with them. When I do read that someone has called, the typical complaint is that the person they speak with is relatively clueless concerning this new unit.
LifeOnEdge, I've agreed with most of your posts about people overreacting to small bugs or unmet expectations (the curse of the early adopter), but if you read the posts, there really does seem to be a problem here with the Colorados not keeping time. Just as the Colorado bashers are overdoing it, you're not helping by being an unmitigated apologist for Garmin.
Everyone just calm down the flames.
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I agree - However, with a steady foot, my GPS and some patience I was able to recalibrate a speedometer when I changed the tire size on a car I used to own. I needed a fast way to do it, popped the dash open and took the needle off the speedometer. Coasted at 5MPH put the needle on then checked it at speeds up to 60. Worked perfect. This did take several attempts as you need a steady foot and flat terrain.
I'm surprised that worked. Changing the tire size will change the ratio, so it will be more incorrect as you increase speed. It's not just an offset (which is what you did by removing and reinstalling the needle). What you probably did was to remove the offset that manufacturers put in to make the speedometers read slightly high by default, so instead it was dead-on.
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The problem with speed readings from a GPS is that it isn't continous or instantaneous. It simply compares where you are now to where you were at the last reading and computes what your average speed was to get you there. Now I do admit that a modern GPS does all of that in under 1 second. That makes it pretty good but not perfect. Radar is doing that same calculation but many times per second.That is why courts do not tend to give much weight to GPS data over radar data.
This is incorrect. A GPS receiver calculates speed using the Doppler shift of the GPS signals, similar to the method used for the radar gun.
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Actually, when you're cruising at 30,000 feet, you still have more than 90% of the atmosphere above you. The part that affects GPS signals the most is the ionosphere, around 100 km up. Even the lowest layer that you're probably thinking of, the troposphere, goes up to about 65,000 feet.
Not to be argumentative, but a 37,000 foot crusing altitude (typical of most commercial flights I've been on lately) is at the top of the troposphere at US latitudes, with 75% of the air mass below. The troposphere only goes up to 65,000 feet in the tropics. According to Wikipedia at least - > http://en.wikipedia.org/wiki/Troposphere
I'm glad you acknowledge that the atmosphere is more than just the thin layer that is the troposphere. I was just correcting your misunderstanding about what WAAS is for. It's to compensate for distortions in the ionosphere, which is still well above you. Air and water molecules and weather in the troposphere have a negligible effect on GPS signals.
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I can't see much use for WAAS though - not only are the atmospheric corrections irrelevant when 90% of the atmosphere is underneath you, but how much accuracy do you need in a position that's changing 900 km per hour?
Actually, when you're cruising at 30,000 feet, you still have more than 90% of the atmosphere above you. The part that affects GPS signals the most is the ionosphere, around 100 km up. Even the lowest layer that you're probably thinking of, the troposphere, goes up to about 65,000 feet.
However, your point about WAAS being useless in this situation is still pretty much right on.
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<snip>
"I don't want to use my tattered 'India for Dummys' translation dictionary to talk with a cs rep ("Good day! How can I help you weeth exceelent service today!...So, you have probleem weeth, washing screen--correect!")"
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Garmin's tech support is based in the US, most likely at their headquarters in Kansas.
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Someone mentioned the magnets in the Rock-n-Roller and wondered if its magnets affected the compass calibration. If so, that would be a huge blunder on Garmin's part. You could probably try it easily--calibrate the compass and test it out, then move the wheel one notch and test it again. Move the wheel back to the original position and see if it comes back (it may not).
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Everyone who has road and/or trail data, please consider contributing it to OpenStreetMap. Check out the project (www.openstreetmap.org) and maybe get involved!
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Can't believe no one has mentioned the main difference - the 60CSx has a quad-helix antenna. The eTrex has a patch antenna. Past experience seems to indicate that a patch antenna of the size used in the eTrex will not perform as well as the quad-helix used in the 60 series. I'm sure the high-performance chip mitigates this difference somewhat. But you only have to go back a few years, prior to either model having the H chip, to see all the post in this forum badmouthing the eTrex patch antenna, as compared to the quad-helix models.
Nobody mentioned it because it no longer matters. Seriously. In fact, a few reviews showed the HCx picking up more satellites, with stronger signals, than a 60CSx under the same conditions.
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How does high temperatures, say 140 degrees F or more affect battery life for ni-mh and alkalines? This past summer I was out all day with my 60CSx and when I got back to the car the batteries were pretty low, so I put in a set of ni-mh that I had charged up the day before, but there were pretty much dead, they had been in the hot car all day. I put in a set of alkalines that I thought were good but they were dead also. They had been stored in the car for a few months.
Generally for batteries, you want to store them at cold temperatures to help retain their charge, but use them at warm temperatures for maximum run time.
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It looks like the HCX is not registering movement unless you are going above a certain threshold speed. You could test this by displaying your current speed and then slowing your speed until it stops seeing the movement.
Miragee was saying it used to be like that. Now with the new firmware upgrade, the Vista HCx is registering more moving time and less stopped time than the 60CSx.
No, not quite
The distance is much closer to the 60CSx compared to the way it used to be, but the Stopped time is greater than actual Stopped time. It seems to be registering speeds slower than some number (1.5 mph, 2 mph ???) as Stopped.Before I installed the new firmware, the distance traveled was less than that of the 60CSx, sometimes by almost 1/3 . . .
Oops, I read them backwards. Looks like they fixed the odometer problem (sort of--they may have overshot) but the same fix needs to be applied to the moving/stopped time.
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It looks like the HCX is not registering movement unless you are going above a certain threshold speed. You could test this by displaying your current speed and then slowing your speed until it stops seeing the movement.
Miragee was saying it used to be like that. Now with the new firmware upgrade, the Vista HCx is registering more moving time and less stopped time than the 60CSx.
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Can't be for the barometer, my Venture Cx has that hole as well. I think it's for sound.
No, it's for the barometer. They use only one case design. On the units without the barometer, it's just a hole.
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By the way, it's not a Sirf Star III chip. It's thought to be a MediaTek, or perhaps something that Garmin has come up with on their own.
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Today while searching for a place to hide a new cache my Vista HCx was showing ±2m precision on the sats screen! I thought the minimum was software blocked to be ±3m.
Anyone else? I don't have a screen capture to show you but next time maybe I'll take a picture.
I wonder if it's because of the new firmware or new sats launched a few months ago?
I noticed that too, after the most recent chipset software update for the Vista HCx. But I'm convinced it's a (newly introduced) display error. I have the EPE set up as a display field on the compass page, and when it's showing 2 m on the sat page, it shows 3 m on the compass page. Further, if I change the units to Statute, it shows +/- 9 or 10 ft on the sat page. That's bigger than 2 m, obviously.
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Hi there!
You all bought this case at amazon? Did you could choose the color? Do you know how many colors are?
Unfortunately they don’t sell to Portugal
regards
AA
I believe that's the only place it's available. Bafflingly, you can't choose the color, and the current available color is a brown/tan.
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I got two of the screen protectors with the case. I'm not sure if that's normal, though, or just a packaging mistake.Can you tell me how many of the little plastic screen protectors did they send with the case?Mine also came with two.
Reading the reviews on Amazon, that appears to be normal.
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Interesting topic, and one I've questioned myself. I've created custom maps with trails, and have often wanted to know how far along the trail I am, and how far I have to go.
Red90: can you enlighten us on how to make a custom map trail routable?
I know a bit about this. The easiest way is to use GPSMapEdit. Load up your custom map (in MP format), then select Tools->Generate Routing Graph->Using Coinciding Nodes of Polylines. This will create all the routes on the trails quickly for you. Then you can edit them manually as necessary. Then do a Tools->Verify Map and fix all the problems that show up. Then, once you have everything fixed, upload it to MapCenter (mapcenter.cgpsmapper.com) and in a short while you should be able to download your routable map img and upload it to your GPS and test it out.
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Check out my review of the Foarm case here
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SiliconFiend,
Thanks for the very informative review.
I have had my eye on this case for my 76CSx and have it saved to my item on Amazon.
Can you tell me how many of the little plastic screen protectors did they send with the case?
And what does the literature say about the warranty ? Is it One year ? Liftetime ?
Thanks, Tim
I got two of the screen protectors with the case. I'm not sure if that's normal, though, or just a packaging mistake. The Amazon page says Lifetime warranty (against defects and workmanship, not necessarily user damage), but I doubt they have to replace very many cases--it's very sturdy.
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For Garmin devices, I believe the National Park 24k Topos have routable trails, but obviously only in their coverage areas.
This has bugged me, too, and it's part of the reason I joined the OpenStreetMap project. Once I get routing working, we should be able to create routable trails as well as roads. No more switching to off-road navigation to get to the cache!
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As English isn't my native language, I'd like an explanation of what's the difference between accuracy and precision in the post by SiliconFiend above. Are you talking about difference from actual position in one case, but variance in the other?
<snip>
As for accuracy and precision, accuracy refers to how close an observation is to reality. For example, if the temperature outside is 12C and your thermometer reads 20C, your thermometer is not accurate. If your thermometer reads 20.00036C, it is precise (can more precisely read the temperature to more decimal places) but not accurate.
You're right about accuracy and close about precision. Precision has more to do with repeatability, although resolution is part of it. Some examples from target shooting (or darts, if you wish): Scatter of marks around the bullseye, in a 5-inch circle: Good accuracy but poor precision. Cluster of marks within a 1-inch circle, offset 3 inches from the bullseye: Good precision but poor accuracy.
Generally, over a short time frame, GPS receivers have better precision than they do accuracy, due to systemic errors (some of which WAAS helps to correct).
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Dude. Backup.
Backup? I had 3 copies. I gave the short story above, but here is the long story.
I was running two drives mirrored as my primary drive. I had a 3rd drive as a backup and used SyncBack to backup my files to the 3rd drive over night. Then my motherboard died. So I put in a new motherboard and Windows would no longer boot up. It would start to boot and then get the BSOD. 
I am guessing that it is because it was using RAID drivers for the old motherboard that aren't compatible with the new motherboard. So I figure since I have 3 copies of everything, I would just wipe one of my previously mirrored drives and do a clean install. So I get Windows up and running again with all the patches. Now it's time to copy my data off the other drive back to my primary drive. Well, where I run XP Pro with multiple logins, it would not let me into my old "My Documents" folder. It was secured and locking me out!
So I panic a little but decided to just get the data off my third drive. Guess what? It says my drive isn't even formatted! Now the panic sets in. One of my three drives was wiped to do a clean install, one says it isn't formatted and the last one is secured and won't let me in. So I went googling. The first item I find tells me how to get in as the machine administrator, grant myself authority to the folders, and get my data!
So now I have most of my data, though it will be a couple days before I figure out what might still be in other places on the old drive.I avoided digital death this time, but it sure has me reconsidering how to safely back up my data from now on. But since I didn't see myself die in the digital world, I don't know if I would die in the real world.
The good news is, my Topo maps were delivered last night and I am reading the 3 sweetest words that can be said together on the UPS site: "Out for Delivery"!
I guess you've discovered that RAID != backup, especially when dependent on a particular RAID controller and drivers. I'm using Linux and software RAID (which has just as good performance as an unaccelerated RAID controller) and has the advantage of working on any Linux install (including a LiveCD). However, despite that, I still have DVDs of all my photos stored in a fire safe at my parent's house, 4 hours away. That should be "offsite" enough. If it's not, we all have bigger problems to worry about.
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I think the point that Anders was trying to make was that averaging can give you a false sense of better accuracy, when in fact just marking the waypoint at a time with an optimal satellite configuration can improve your accuracy much more.
Except the Garmin unit ALSO display a continual estimate of the averaged accuracy. This lets you know if the averaging is making things better or worse. It works very well.
Yes, I've used the function myself and agree that it's useful and should be included in the Colorado. There's a funny (confusing) thing about that function, though. Averaging should never make the accuracy worse (the average should be converging on the true location as more samples are collected), but it may make the precision worse, in the near term (if the reported EPE is increasing while you're averaging).
The distance is much closer to the 60CSx compared to the way it used to be, but the Stopped time is greater than actual Stopped time. It seems to be registering speeds slower than some number (1.5 mph, 2 mph ???) as Stopped.
I was running two drives mirrored as my primary drive. I had a 3rd drive as a backup and used SyncBack to backup my files to the 3rd drive over night. Then my motherboard died. So I put in a new motherboard and Windows would no longer boot up. It would start to boot and then get the BSOD. 
I am guessing that it is because it was using RAID drivers for the old motherboard that aren't compatible with the new motherboard. So I figure since I have 3 copies of everything, I would just wipe one of my previously mirrored drives and do a clean install. So I get Windows up and running again with all the patches.
Need help with e00 file
in GPS technology and devices
Posted
I've had good luck with ogr2ogr which you can download here (FWTools). It's great for converting between different formats, and for converting datums and projections.