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Sam Wormley · Guest

Linea Recta wrote:
[quote]I>ve been using GPS for some time (TT navigator & iGo op PPC) and quite
satisfied with my experences.
But... I still don>t understand clearly the difference between the
following terms:

- routes
- tracks
- waypoints

Thanks for good explanations.

[/quote]

Waypoint - A specific location (coordinates) saved in a receiver>s
memory.

Route - A sequence (determined by the user) of stored waypoints.

Track - The direction of movement relative to a fixed position

There may be slightly different definitions of the words, But Garmin
and Trimble tend to agree with the Institute of Navigation (ION)
For more, see:
http://www.google.com/search?q=GPS+Glossary

Tom H. · Guest

"Sam Wormley" <swormley1@mchsi.com> wrote in message
news:_XVfk.258653$yE1.141505@attbi_s21...
[quote]Linea Recta wrote:
I>ve been using GPS for some time (TT navigator & iGo op PPC) and quite
satisfied with my experences.
But... I still don>t understand clearly the difference between the
following terms:

- routes
- tracks
- waypoints

Thanks for good explanations.

Waypoint - A specific location (coordinates) saved in a receiver>s
memory.

Route - A sequence (determined by the user) of stored waypoints.

Track - The direction of movement relative to a fixed position

There may be slightly different definitions of the words, But Garmin
and Trimble tend to agree with the Institute of Navigation (ION)
For more, see:
http://www.google.com/search?q=GPS+Glossary
[/quote]
Many people refer to tracklogs as tracks, in which case the definition is
something like this "a record of where the unit has been as recorded over
time (and distance)".

--
Tom
http://home.att.net/~tbharvey/

Sam Wormley · Guest

Tom H. wrote:
[quote]"Sam Wormley" <swormley1@mchsi.com> wrote in message
news:_XVfk.258653$yE1.141505@attbi_s21...
Linea Recta wrote:
I>ve been using GPS for some time (TT navigator & iGo op PPC) and quite
satisfied with my experences.
But... I still don>t understand clearly the difference between the
following terms:

- routes
- tracks
- waypoints

Thanks for good explanations.

Waypoint - A specific location (coordinates) saved in a receiver>s
memory.

Route - A sequence (determined by the user) of stored waypoints.

Track - The direction of movement relative to a fixed position

There may be slightly different definitions of the words, But Garmin
and Trimble tend to agree with the Institute of Navigation (ION)
For more, see:
http://www.google.com/search?q=GPS+Glossary

Many people refer to tracklogs as tracks, in which case the definition is
something like this "a record of where the unit has been as recorded over
time (and distance)".

[/quote]
I agree.

Uwe Hercksen · Guest

Jack Yeazel schrieb:
[quote]
Due to the difference in the British GB36 and WGS-84 datums, the two
lines diverge as one travels north from the equator...
[/quote]
Hello,

marking the intersection of the equator and the prime meridian may
require a research submarine:
http://confluence.org/confluence.php?lat=0&lon=0
dropping a steel ball from a boat is not precise enough...

Bye

jaf · Guest

Since when can the FCC enforce their REGULATIONS in other countries or foreign armies?
Get a bigger box of tin foil.

"peter" <prathman@comcast.net> wrote in message news:e005c053-9d9d-4bd9-814d-d605144b81c0@8g2000hse.googlegroups.com...
On Sep 30, 11:58 am, nos...@de-ster.demon.nl (J. J. Lodder) wrote:
[quote]nickw7...@gmail.com <nickw7...@gmail.com> wrote:
[/quote]
I>d expect most circumventions of GPS devices installed for such
purposes to take the form of signal blocking rather than jamming
(would generally violate FCC rules) or spoofing (also in violation of
FCC rules and technically difficult). Any piece of metallic foil over
the antenna can effectively block the satellite signals and there are
an almost endless number of ways in which the GPS receiver and/or
antenna can be made to mysteriously fail.

Jack Yeazel · Guest

Uwe Hercksen wrote:
[quote]
Jack Yeazel schrieb:

Due to the difference in the British GB36 and WGS-84 datums, the two
lines diverge as one travels north from the equator...

Hello,

marking the intersection of the equator and the prime meridian may
require a research submarine:
http://confluence.org/confluence.php?lat=0&lon=0
dropping a steel ball from a boat is not precise enough...

Bye
[/quote]
Yeah, that>s the standard 'gag'... I suppose it was all done with
mathematics...

However, the actual basics of WGS-84 zero Long. has to do with many
survey pins on all the continents... It is based on the AVERAGE
location of the land masses as they 'float' around the world... That>s
why the call it "World"...

Surveying in the US is based on NAD-83 which is a datum that 'falsely'
assumes the US isn>t drifting with respect to WGS-84... That way, Lat.
Long. of a particular point is more 'stable' than if based on WGS-84...

Here in Atlanta the difference is about 2m -within the range of
detraction with a quality hand-held unit and waypoint averaging...

--
Jack

Get general GPS information at: http://www.gpsinformation.net/

null · Guest

"128" <yougu_ok@163.com> wrote in message
news:77ecafbb-b4aa-42d5-bace-ec75b97ba0e4@z11g2000prl.googlegroups.com...
[quote]jeans:
cheap EVISU jeans wholesale www.honest-shop.cn
snip[/quote]

Hmm, I would guess that the OP does not understand the full connotation of
the word "cheap" in the English language.

And "honest-shop"; well nuff' said there...

ps56k · Guest

"Bill Smith" <kb3gun-nospam1@wpia.net> wrote in message
news:48eceaca$0$7366$ec3e2dad@news.usenetmonster.com...
[quote]
"Patrick, Whit" <wcpatrick@cencoast.com> wrote in message
news:C512302F.23405%wcpatrick@cencoast.com...
I apologize in advance for cross-posting.

Does anyone know of any discussions in other groups regarding the Spot
Messenger device? I am thinking of buying several for our workers who
work
alone in remote locations.

The manufacturer describes the device this way, " SPOT is the only device
of
its kind, using the GPS satellite network to acquire its coordinates, and
then sending its location with a link to Google Maps and a
pre-programmed message via a commercial satellite network."

I think it qualifies for a GPS discussion, but perhaps not THIS
discussion.

Disclaimer: I have no financial interest in this product other than not
wanting to spend money for a product that won>t work for our needs.

Thanks!

I>ve looked at it and it>s a great idea. Much like APRS for amateur radio
(but easier and no license required). Price looks reasonable too. We>re
looking at purchasing a few for search & rescue activities to help track
the search progress from the EMA office.
--
Smitty
Somerset, PA
I was interested in learning about the SPOT device[/quote]
as mentioned on TV and in Backpacker magazine.

There were some online articles that I found
that compared it to the standard 406Mhz PLB devices,
along with the differences in the overhead satellite coverage
and the differences in the emergency services that are contacted.

Also - do you want the tracking ability of the SPOT,
or are mostly interested in the 911 type of emergency call ?

Spot PLB -

http://www.findmespot.com

406 MHz PLB -
http://www.acrelectronics.com/PLBorig/gypsi.html

Roy Lewallen · Guest

There>s been some discussion of the SPOT on the AOPA Forums. I haven>t
read the threads, but see
http://forums.aopa.org/search.php?searchid=1976826 for a few of them.

I took a SPOT along on a trip to Alaska this summer with a friend in his
homebuilt plane. It worked great in the auto mode, posting our position
every 10 minutes to a web site where family and friends could track our
progress. After the trip I got many comments about how much the folks
liked being able to see where we were. I sent an explicit Ok message a
few times, and it was transmitted and the proper people contacted. We
went as far north and west as Fairbanks and Nome, and it worked fine
even at those extremes. Experiments at home in Oregon, though, indicate
that it needs a pretty clear shot at the sky. So it might not help you
out as an emergency locator if you were in a valley in mountainous
country, for example and couldn>t get to a better place. But if you use
the auto mode, at least the last good position would have been recorded.

Our trip lasted about a month, and the unit was on in its auto mode
whenever the plane was in the air and often when it was on the ground
waiting for weather to clear, etc. And there>s still a fair amount of
energy left in the one set of lithium batteries we used.

I feel I got more than my money>s worth out of it, and highly recommend it.

Roy Lewallen

ps56k · Guest

here>s the thread I had over the summer in the SAT NAV newsgroup -
BTW - Is there any other way to "reference" a previous newsgroup thread ?

http://groups.google.com/group/sci.geo.satellite-nav/browse_thread/thread/a1a5dd1da4c7e814/ae39d2e2452d836a?lnk=st&q=spot+locator+#ae39d2e2452d836a

Jack Erbes · Guest

ps56k wrote:
[quote]here>s the thread I had over the summer in the SAT NAV newsgroup -
BTW - Is there any other way to "reference" a previous newsgroup thread ?

http://groups.google.com/group/sci.geo.satellite-nav/browse_thread/thread/a1a5dd1da4c7e814/ae39d2e2452d836a?lnk=st&q=spot+locator+#ae39d2e2452d836a

[/quote]
Right click on the post, click on Copy Message Location, then paste that
into an email or document.

Your post is at:

news://news.motzarella.org:119/eE8Hk.2034$W06.307@flpi148.ffdc.sbc.com

Jack

Jack Erbes · Guest

Jack Erbes wrote:
[quote]ps56k wrote:
here>s the thread I had over the summer in the SAT NAV newsgroup -
BTW - Is there any other way to "reference" a previous newsgroup thread ?

http://groups.google.com/group/sci.geo.satellite-nav/browse_thread/thread/a1a5dd1da4c7e814/ae39d2e2452d836a?lnk=st&q=spot+locator+#ae39d2e2452d836a

Right click on the post, click on Copy Message Location, then paste that
into an email or document.

Your post is at:

news://news.motzarella.org:119/eE8Hk.2034$W06.307@flpi148.ffdc.sbc.com

Jack
[/quote]

And replying to my own post, I should have said that "your post in
contained in the thread at", the link is to the thread, not the
individual posts.

Jack

Guest · Posted: Fri Oct 10, 2008 12:36 am Post subject: Re: Spot Messenger Discussions?

On Oct 8, 1:22 pm, "ps56k" <pschuman_no_spam...@interserv.com> wrote:
[quote]"Bill Smith" <kb3gun-nosp...@wpia.net> wrote in message

news:48eceaca$0$7366$ec3e2dad@news.usenetmonster.com...

"Patrick, Whit" <wcpatr...@cencoast.com> wrote in message
news:C512302F.23405%wcpatrick@cencoast.com...
I apologize in advance for cross-posting.

Does anyone know of any discussions in other groups regarding the Spot
Messenger device? I am thinking of buying several for our workers who
work
alone in remote locations.

The manufacturer describes the device this way, " SPOT is the only device
of
its kind, using the GPS satellite network to acquire its coordinates, and
then sending its location with a link to Google Maps and a
pre-programmed message via a commercial satellite network."

I think it qualifies for a GPS discussion, but perhaps not THIS
discussion.

Disclaimer: I have no financial interest in this product other than not
wanting to spend money for a product that won>t work for our needs.

Thanks!

I>ve looked at it and it>s a great idea. Much like APRS for amateur radio
(but easier and no license required). Price looks reasonable too. We>re
looking at purchasing a few for search & rescue activities to help track
the search progress from the EMA office.
--
Smitty
Somerset, PA

I was interested in learning about the SPOT device
as mentioned on TV and in Backpacker magazine.

There were some online articles that I found
that compared it to the standard 406Mhz PLB devices,
along with the differences in the overhead satellite coverage
and the differences in the emergency services that are contacted.

Also - do you want the tracking ability of the SPOT,
or are mostly interested in the 911 type of emergency call ?

Spot PLB -

http://www.findmespot.com

406 MHz PLB -http://www.acrelectronics.com/PLBorig/gypsi.html
[/quote]
I have a "spot", but only use mine for a position report, generally
where I camp at night. It works fine, even under a canopy of trees.
You have 3 types of reporting:
1) OK
2) preprogrammed help message
3) the fecal matter has hit the fan, send help

Message number 2 is for what I would call a soft emergency. Say your
vehicle breaks down in the middle of nowhere, or worse yet, off road.
I program the message with the phone number of the highway patrol in
the state that I am in.

You can program a message for the OK mode as well. This is a good
thing to do so that nobody on the receiving end freaks when they get
the message.

The problem with a 406 beacon is you only have the "fecal matter hit
the fan" mode. You can>t check in. Now the spot is cheaper than a
beacon, but there is the subscription cost. Also, the 406 beacon is
reacted to by the feds, while the spot uses the private sector to
notify the feds.

I generally don>t buy generation one of anything, but I found the spot
useful enough that I got one. I expect next generation devices to come
along, but if you are really hanging out in remote areas, better to
spend the money now and then again rather than wait.

Tim Springer · Guest

Hi Fashouri,

An interesting field in GNSS right now and for the coming years is what is called "precise point positioning (PPP)". The
difference between the "normal" use of GNSS is that contrary to usign broadcast ephemerides you use higly precise orbits and
clocks. With that high precision information you can determine the position of your receiver (or rather the phase centre of your
antenna) at the centimetre or even millimetre level, i.e., a very precise estimate of your "point". Hence the name PPP.

To reach such accuracies you must, however, get the modelling of the signal propagation, your station position, and your receiver
clock at the (sub)millimetre level. So, it is a nice thing to start working on. If you get it to the decimeter level and
university should be interested in admitting you to a MSc course in a related area!

By the way. Precise orbits and clocks can be obtained from the IGS service (http://igs.org) as well as tons of receiver tracking
data from sites all over the world (and even in Iran).

For more information on PPP just do a google search and read some of the papers you find :)

Cheers,
Tim.

"farzin" <fashouri@gmail.com> schrieb im Newsbeitrag news:be029be0-63ed-4e8a-aacb-ffb72779fb35@f36g2000hsa.googlegroups.com...
[quote]
I>m from Iran and I>ve got BSc in Geomatics Engineering
Now I want to do some research but as I>m far from academic
environment and I don>t have access to professors to guide me directly
I don>t know what to do
and how to start.
I want experts in this forum to help me find some new research topics
which I can use them as building blocks to be admitted in a credible
university in an
MSc course.
I am interested in Global Warming, GPS and I>m keen on Geodesy and
GIS
I know MATLAB and Autodesk Land desktop well
I should be grateful if you could help me[/quote]

ps56k · Guest

Jack Erbes wrote:
[quote]Jack Erbes wrote:
ps56k wrote:
here>s the thread I had over the summer in the SAT NAV newsgroup -
BTW - Is there any other way to "reference" a previous newsgroup
thread ?

http://groups.google.com/group/sci.geo.satellite-nav/browse_thread/thread/a1a5dd1da4c7e814/ae39d2e2452d836a?lnk=st&q=spot+locator+#ae39d2e2452d836a

Right click on the post, click on Copy Message Location, then paste
that into an email or document.

Your post is at:

news://news.motzarella.org:119/eE8Hk.2034$W06.307@flpi148.ffdc.sbc.com

Jack

And replying to my own post, I should have said that "your post is
contained in the thread at", the link is to the thread, not the
individual posts.

Jack
[/quote]
FYI - what news reader software are you using ? I>m using Outlook Express.

The "right click" only appears to be valid for your specific software,
as I>m using Outlook Express and don>t see the "copy message location".
Also - since we all are using different news servers provided by our ISP,
or may be using a private subscribed to service,
the actual URL is only valid for your news server....

That>s why I went to Deja / Google Groups - as there doesn>t seem to be any
other generic way -


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