Followers 16

## Recommended Posts

But elevation is needed for the 4th dimension. Hence 4 satellites.

Why do you need elevation to determine time?

Doh! Finally.. my head is working properly. I don't know why it took me so long to clue in on this one.

Thanks!

But elevation is needed for the 4th dimension. Hence 4 satellites.

Why do you need elevation to determine time?

I think the problem is ambiguity between whether the original question was "How many satellites are needed to determine THE 4th - D?" and "How many satellites are needed to determine ALL 4 -D's?"

I thought the question was the latter of the two.

either way you won - Is there another question on the table?

either way you won - Is there another question on the table?

Oh,

Sorry, I thought things had moved on with the question of what the area between the ground and the canopy was called.

If that question is still on going, please disregard my question.

In honour of the Olympics, what is the Olympic motto? (Latin or English will be accepted.)

That one is pretty easy seeing as how the Olympics are in our back yard out here :-)

Swifter, Higher, Stronger

That one is pretty easy seeing as how the Olympics are in our back yard out here :-)

Swifter, Higher, Stronger

A little further than my backyard, here in Ontario

But you are right, collect your gold medal, and start the next event, I mean question

Okay, this one shouldn't be too bad ....

In GPS terms, the acronym DOP means Dilution of Precision. There is another acronym that

references the same condition. What is it, and what does the acronym stand for?

Okay, this one shouldn't be too bad ....

In GPS terms, the acronym DOP means Dilution of Precision. There is another acronym that

references the same condition. What is it, and what does the acronym stand for?

Geometric Dilution of Precision (GDOP)????

Okay, this one shouldn't be too bad ....

In GPS terms, the acronym DOP means Dilution of Precision. There is another acronym that

references the same condition. What is it, and what does the acronym stand for?

Geometric Dilution of Precision (GDOP)????

Please, no off-topic questions. Until Geocaching becomes an Olympic sport any questions pertaining to it are off-topic.

BTW, I think Juicey's question is incorrect. 2 points define a line, 3 points a plane and 4 a volume. Even a plane has dimensions, although it could be argued a line doesn't.

BTW, DOP is a general term for many different measurements. So my answer is also general and is "Location Error".

My question may be a little sideways and hence difficult to answer, but I was looking for EPE - Estimated Position Error.

I'll leave it to you guys to determine who will ask next.

Okay then try this one ...

Civilian GPSRs are restricted in both the speed and altitude at which they will operate.

Please state either the maximum speed of travel allowable OR the maximum altitude allowable by the US military in order to use your civilian GPSr.

My Old Magellan Meridian Gold use to max out at 999 km/hr but didn't go any further since it only had 3 digit for speed.

Don't ask how I found that out.

Okay then try this one ...

Civilian GPSRs are restricted in both the speed and altitude at which they will operate.

Please state either the maximum speed of travel allowable OR the maximum altitude allowable by the US military in order to use your civilian GPSr.

18km.

LeftCoastCachers has the point and the next question.

60,000 feet or 18.xxx km is the maximum altitude usable by a civilian GPSr.

For the record, 900 knots is the maximum allowable speed for a civilian GPSr. which equates to approximately 1666.75 kph.

Just out of curiosity, is the maximum altitude a limit of the technology or more for political reasons?

As for the maximum speed, I can see this as perhaps a Doppler-shift issue.

As I understand it, the limits placed on civilian units are in relation to real time signal acquisition discrepancies. I am not really versed in military specs, but error checking is much more precise with high-end military units and as such would give them a huge precision advantage over civilian units. For example, a cruise missile can be directed precisely through a 3 foot by 3 foot window in the side of a building while moving at mach speeds. We will not see that kind of accuracy while on the move in a civilian GPSr.

While Doppler is more specific to sound and ultra sound, the result is similar where the signal strength and accuracy will change dependent on the speed and altitude in relation to the source.

I came across the information while researching the outer edges of what these things are capable of.

As I understand it, the limits placed on civilian units are in relation to real time signal acquisition discrepancies. I am not really versed in military specs, but error checking is much more precise with high-end military units and as such would give them a huge precision advantage over civilian units. For example, a cruise missile can be directed precisely through a 3 foot by 3 foot window in the side of a building while moving at mach speeds. We will not see that kind of accuracy while on the move in a civilian GPSr.

While Doppler is more specific to sound and ultra sound, the result is similar where the signal strength and accuracy will change dependent on the speed and altitude in relation to the source.

I came across the information while researching the outer edges of what these things are capable of.

Doppler effects can influence radio waves for sure... and pseudo doppler effects can be used to track things.

However it is unlikely to effect GPS, since the system uses transmitted data and time information.

Your GPS reciever/processor unit reads the data transmitted by the satellites, compensates for transmisson time differences for all stations involved, and calculates its position based on that data. Since Doppler isn't involved in that process, it isn't a factor at all. The satellites transmit their orbital position information which is calculated from the Keplarian data that defines their orbits... in other words, if right now is xxx.xxxxx o'clock I must be at a certain specific point in my orbit. You get that position calculation, and a time.

Adjust for time differences and then you can calculate your position etc.

As for the altitude bit... aside from unit display capacity, there are signal distortions that can occur when the angle of the satellite is fairly flat, for example, look at days when all the satellites seem to be low to the horizon... not very useful for navigation. The atmosphere scatters the signal. Again Military units have more frequencies to play with and better ways to correct such errors... You get what you pay for I guess.

Our newer civilian rigs are much better than what I use... that was 90's tech, it works, but had all sorts of limits compared to now, such as a partially incomplete constellation... often had to wait for useable satellites to come into range... not to mention SA. Still good for our purposes, but I do wish I could get something newer on a full time basis. As for the speed limits... display capacity for sure, and the fact that civilians were not supposed to have access to things even that fast... of course with civilian's buying surplus jet fighters now... even old ones who knows. not to mention civilian spacecraft.

Doug

Thanks for that clarification. I am just scratching the surface of how these things work. It's all pretty fascinating to me.

LeftCoastCachers has the point and the next question.

Okay...here might be a relatively easy one.

What holds the record as the largest act of peaceful civil disobedience in Canadian History?

Although on the surface it might not seem like a geo-related question, it is....at least I think so.

Okay...here might be a relatively easy one.

What holds the record as the largest act of peaceful civil disobedience in Canadian History?

Although on the surface it might not seem like a geo-related question, it is....at least I think so.

Can this onion ring get more fans then Stephen Harper?

Okay...here might be a relatively easy one.

What holds the record as the largest act of peaceful civil disobedience in Canadian History?

Although on the surface it might not seem like a geo-related question, it is....at least I think so.

Can this onion ring get more fans then Stephen Harper?

*chuckle* No, but I AM a member of that group.

Nope, the act of civil disobedience consisted of 12,000 people and resulted in over 850 arrests.

I just couldn't stand to see Canadian Geopub Quiz so far down the page. "Moon the Balloon" sounded awesome! Those wacky Sarnians. I see no evidence on the web that the balloon is still spying.

I suppose the real answer was some sort of environmental protest, if it were to be somewhat Geocaching related.

I just couldn't stand to see Canadian Geopub Quiz so far down the page. "Moon the Balloon" sounded awesome! Those wacky Sarnians. I see no evidence on the web that the balloon is still spying.

I suppose the real answer was some sort of environmental protest, if it were to be somewhat Geocaching related.

Since I seem to have stumped everyone, the answer is the Clayoquot Sound logging protests of 1993.

TheWhiteUrkel was closest, so next question is yours!

I just couldn't stand to see Canadian Geopub Quiz so far down the page. "Moon the Balloon" sounded awesome! Those wacky Sarnians. I see no evidence on the web that the balloon is still spying.

I suppose the real answer was some sort of environmental protest, if it were to be somewhat Geocaching related.

Since I seem to have stumped everyone, the answer is the Clayoquot Sound logging protests of 1993.

TheWhiteUrkel was closest, so next question is yours!

What? Me? I'm not even friggin' Canadian! But I do live on the border, and have about 400 finds in Ontario.

So with that in mind, I've come up with one. Before the now meaningless preliminary round game of 21 February 2010, when was the last time Canada lost to the U.S. in an Olympic Hockey game? The year/Olympiad is fine for an answer.

pffft, we don't pay attention to our losses

Since I seem to have stumped everyone, the answer is the Clayoquot Sound logging protests of 1993.

Y'know, I shoulda known that... it was where the Raging Grannies first gathered. (Where I got the name 'hamgran'). Sheesh!

Edited by hamgran

pffft, we don't pay attention to our losses

Be nice to the American. Or you might just have your first international cache that mocks you.

Well, the announcers mentioned this about 50 times during the Olympics. Then again, that was American TV. I seem to have lost the ability to get CTV or CBC any more, since I went to a dish a couple of years ago.

Ah, just saw this post ... I believe it was 1998 ... if you're talking tournament, I'm pretty sure the American team won it in '98

Memory is fuzzy about whether they beat the Canadians to take it though ... must resist the Google.

Ah, just saw this post ... I believe it was 1998 ... if you're talking tournament, I'm pretty sure the American team won it in '98

Memory is fuzzy about whether they beat the Canadians to take it though ... must resist the Google.

I can't remember when the last time was (Google is tempting but I'll resist), but it was a lot longer ago than 1998. I think it was 1960 or something like that...

Anyway, I know the Czechs took gold in Nagano, and that neither Canada nor the US even medaled!

Ah, just saw this post ... I believe it was 1998 ... if you're talking tournament, I'm pretty sure the American team won it in '98

Memory is fuzzy about whether they beat the Canadians to take it though ... must resist the Google.

I can't remember when the last time was (Google is tempting but I'll resist), but it was a lot longer ago than 1998. I think it was 1960 or something like that...

Anyway, I know the Czechs took gold in Nagano, and that neither Canada nor the US even medaled!

I'll take something like that! 1960 it is. Seeing as I can use Google, it was February 25, 1960 US 2 Canada 1. The U.S. won the Gold in 1960. Their only other Gold, in 1980, the U.S. and Canada did not play each other. Over to you, Taoisearch.

I suppose I'll as a follow up question

Who won gold in Olympic (ice) hockey in 1936?

I suppose I'll as a follow up question

Who won gold in Olympic (ice) hockey in 1936?

The Ottoman Empire?

You are sort of on the right track though... sort of...

Great Britain! I'm just lurking... someone ask away

Correct!

The floor is open

If you were traveling in Canada, where would you find this sign?

Lorne

I was going to attempt to be funny and answer "on the roadside" but something about the fact that it's attached to rocks instead of the posts being dug into the ground makes me doubt that.

So instead I'm going to make a wild guess...(beside train tracks) going thru the Fraser Canyon?

You are in the right province. It is part of the history of BC.

Hmmm - with your clue, and looking at your home location, I'm going to say Barkerville (Barkersville?). Never been there but I've driven by the signs many a time.

Hmmm - with your clue, and looking at your home location, I'm going to say Barkerville (Barkersville?). Never been there but I've driven by the signs many a time.

nope

Its in the Rockies. Next question!

What was the name of the movie that featured geocaching, and starred a woman with the geoname "Galaxy"?

Geocaching, The Movie? (just a guess)

If you were traveling in Canada, where would you find this sign?

Lorne

It is on the Bella Coola Hill. It marks the spot where the two cats touched blades, opening up the road to Bella Coola.

Lorne

What Canadian geocacher has placed a geocache in England that currently has 70+ watchers and is closing in on 5,000 Finds?

What Canadian geocacher has placed a geocache in England that currently has 70+ watchers and is closing in on 5,000 Finds?

oh, oh, I know this one, both the answer and the cacher. but I don't have a followup question so I'll leave it for someone else to have fun with. I hope to one day get as many of his capital caches as is now possible.

What Canadian geocacher has placed a geocache in England that currently has 70+ watchers and is closing in on 5,000 Finds?

oh, oh, I know this one, both the answer and the cacher. but I don't have a followup question so I'll leave it for someone else to have fun with. I hope to one day get as many of his capital caches as is now possible.

Me too! But I would also be out hunting for a new question for a while, so I'll leave it.