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Qstarz Travel Recorder BT-Q1000P for sale
Well, it's not a bike but a valuable accessory to track rides, drives, hikes and even flights.
More info on the product here.
http://www.qstarz.com/images/DM/1000P-eDM.jpg
Asking price: RMB 888 :icon10: (includes free shipping in Mainland China)
It should still have warranty until October 2009
Anyone interested pls. let me know.
Andy
Hi Andy,
I'm interested. But only if this device makes tracks with the real coordinates, not the chinese coordinates. I have a Chinese Version of the Garmin 60CSx with Chinese maps (in Pinyin) which is great to fiond roads and places. But it records the tracks with the wrong chinese coordinates, means if I transfer the tracks to google earth or other programs that are using the real, right, non-chinese coordinates, the track is always a few hundret meters wrong. Thus I need a second one, a simple one which just records the real, true coordinates.
Can I sychronize this with my PC? Can I sychronize to Google Earth?
BTW: Tim, Andy Hall, Russel and I wnat to set up a frequent meeting of Beijing's Bikers. Most probably at Frank's Place, once a month. Since Tim & Co are not as often around town, they will coordinate when exactly. Switch to http://bg-performance.ning.com/group/beijingridersgroup and you will see. Or call Tim. Would really be nice if we all can meet up some day. And ask your fellow rubbercow-boy to join in. The more he better...
Call me for the GPS stuff: 13501217191
Every GPS device works with "real" coordinates, unless it is made by the CPC or PSB - and I doubt that they are able to make one at all :lol8::lol8::lol8:Quote:
Originally Posted by peterkue
As we all (hopefully :lol8::lol8:) know, our planet is neither a disc, nor a sphere. Most commonly we know mother earth to be an ellipsoid.
But this isn't really true either. Considering mountains, high plains, the oceans and other geographical features, our home actually is a potato of similar shape as an ellipsoid would be. Early cartographers used a flat surface, ideally given by water - the water level - for their measurements. Water follows gravity, which is different in different areas, depending on the density and nature of material, mostly way under the surface (of a landscaper :lol8::lol8::lol8::lol8:)
There is something like an ideal ellipsoid, based on the earth's center of mass, and there are many ellipsoids in different areas with certain x-y-z deviations from this ellipsoid according to the local gravity circumstances.
This "ideal" ellipsoid was at the latest defined in 1984 and is called WGS84 (World Geodetic System 1984). All, or most, other local systems are based on WGS84, by defining several parameters of deviation such as, but not limited to, x, y, z.
All modern GPS receivers work with coordinates based on WGS84, and not even the Chinese government can change this :naughty::naughty::naughty:.
What can be influenced, and what in fact is influenced, are the maps you would draw the coordinates on, which you read from your GPS.
This is definitely true for Google Maps and it's Chinese "daughter" ditu.google.com. There is not much of a deviation (something like 20 to 100 meters), but enough to bother you when you know that you have been riding perfectly on the road. Reasons for this intended deviations remain unclear (at least for me). Some say the military is interested to send you off the road (which I wouldn't mind :lol8::lol8:), some say it has commercial reasons.
I compared Google maps with Baidu and Sogu maps. Google maps are free to use with the API provided by Google but inaccurate (at least) in China. Baidu and Sogu are perfectly accurate (if you manage to get hands on them and calibrate them), but there is no API, nor documentation.
Google Earth however, mostly fits perfectly unless they have matching or aligning errors in their Sat pics.
Now to you questions (finally :rolleyes1:)
- The device records WGS84 coordintes
- it can be synchronized with Google Earth
- Track memory is 200000 points (enough for 10000+ kms depending on recording settings)
- downloadable to your PC (software comes with it)
- rechargeable battery (lasts for over 20 hrs)
Quote:
Originally Posted by peterkue
I thought about such a gathering as well but there are several already.
I think we should try to coordinate those (at least quarterly) to get the community together.
Let's see i'll get in touch with Tim.
Andy
Thanks Andy, "finally we got the answer from a professional :thumbsup:Quote:
Originally Posted by chinabiker
I didn't believe it was that scientific :lol8::lol8:"
Although we discussed this already over the phone today, it might be of interest for others: Most of "chinese GPS", even those from Garmin, Magelan etc use wrong coordinates. By writing "Chinese GPS" I mean those that are officially bought here in China. The Device and the maps. Both, the Device and maps fit together, so you can use it very well, it shows you exctly on which street you are, which road you have to take, where to make turn etc to reach your target.
I had my first doubts, when I went off-Road in the desert with some chinese friends and one of the group got lost. As I was the only one in my gruop with a GPS, the lost one asked via walky-talky about our position. But I had a Garmin GPS, bought in Germany, showing the true coordinates. When the other one took my coordinates to find us, he ended up a few hundret meters away from us (but found us). When we compared our coordinates, we found that his differed from mine. However, at that time I only used the Garmin World map, a very rough map showing about 5 streets in Beijing. But it was ok for Off-Road in the desert, to download my tracks into Google Earth etc.
Later this GPS broke and I bought a new one. Again Garmin, but a newer, better device. I bought it here in Beijing, a cracked version without warranty (thus 4000 instead of 8000 RMB). I also bought an official Chinese Map directly from the official Chinese Garmin importer, everything translated into Pinyin, so that I can read the addresses. It works pretty well, btw.
But when I synchronized this device, uploading my old tracks into this one, my house, my office, tracks, POI's, everything moved about 300-400 meters east north east. Sometimes more, sometimes less.
When complaining about this at the Garmin Importers office, he admitted this, he said that this is required by the Chinese Government.
Frankly, I am not surprised, we know how paranoid they can be, but it's also very childish. Do they really believe an Invader (Japs, Taiwanie, Amis, ... Don't know what or whom they have in mind...) or "terrorist" from T---t or elsewhere (inside or outside China) would buy a GPS device in China, setting the missile coordinates accordingly and then.... Boooooom?
I guess even the most stupid guy (with this kind of ideas) knows google earth, but would surely not rely on this only.
And that's why I need such a tracker like you offer here. To download my track accurate to Google Earth and other programs, to share them with others, etc. But then I have two things on my dashboard/steering bar... "great".
Sorry Andy, maybe all the stuff I wrote was a bit confusing: Yes, I want to buy this device. Bring it next Tuesday to Frank's Place, please.Quote:
Originally Posted by chinabiker
Hi Peter,
I have this unit and I really like it. When you complete a ride, you can download the data in many file formats. If you save a kml file and open it in google maps, the coordinates will be correct but the maps will be slightly offset. Satellite view will look correct, but the map view will be a little off. If you export your track as a text file and then open it in Excel, you can subtract .0025 degrees from the latitude coordinates and add .0051 degrees to the longitude coordinates. This will line up perfectly with the Chinese maps.
Here is an example, you can download this KMZ Offset Example
Let me know if you have any questions, I've been using the 1000P for a long time.
Cheers
ChinaV
Thanks ChinaV for this useful information. I opened your KMZ with Google Earth. My question is: Which track is the one you took with the 1000P? The Red or the Green one? The Green one follows the roads quite precisely, while the red one has the same offset as I have with my Garmin device that I bought here in Beijing.Quote:
Originally Posted by ChinaV
Or did you take the red track with the 1000P and and after the conversion, that you described above you got the green track? My previous Garmin that I once bought a couple of year ago in Germany also showed the track very precisely in Google Earth.
Have you purchased your 1000P in China (Mainland)?. If so, and if the red track is the one you got from this device, I am pretty sure, that your 1000P works with the same "wrong" coordinates as all "officialy-in-China-purchased" GPS devices do. I'm wondering where Andy bought his 1000P. He is German, most likely he bought it in Germany, so it should show the "real" coordinates, which I can directly (without conversion) see (at the right location) in Google Earth.
However, your hint with the conversion of the coordinates via Excel is excellent (Now I know why Microsoft chose Excel for this program. They are behind this not the Chinese Gov or Military. Sorry guys ;-).
I will try it out later and let you know if it worked with my "China-bought-GPS" as well.
Anyway, I assume that I will buy Andy's device. I'll meet him next week here in Beijing, we know each other already for quite a while, so I think he will borrow it to me for couple of days for testing. I cecked a few reviews in the internet, looks as if this exactly what I need. Even if I can convert the "wrong Chinese Coordinates" with your little trick into the right ones. Because there's one feature in it, which I find very nice: You can synchronize digital photos with it, means you will have the coordinates later in your photo properties. That's useful if you want to see where exactly you took your photos.
Peter
Peter,
You will really enjoy having your photos geo-tagged, turns your camera into a notebook for remembering road numbers, conditions and important spots :thumbsup:.
The green track is the recorded track from my 1000P, I purchased it in Hong Kong. I'm 99 percent sure it's the same as yours. The red track was calculated from the green track.
Thank you for sharing your experience with the Garmin, you and Andy have answered a question sitting in my brain for a long time about what goes on with the China/non-China units.
Chinese GPS units apply an offset to the coordinates that matches the offset used by Chinese map companies. Non Chinese GPS units use real coordinates that display incorrectly on Chinese maps. :frump: The fact that I am able to understand this makes it seem silly that the issue even exists.
Cheers!
ChinaV
Sure, no problem you can have it for testing. Please also bring your Chinese 60CSx and I'll make a test with a bunch of devices.Quote:
Originally Posted by peterkue
See you
Andy
Sure, Andy, I'll bring my Chinese Garmin 60 CSx along.Quote:
Originally Posted by chinabiker