Outdoor Pursuits

maybe the accuracy of the satelite pictures are not as good in the forrests as in the city since less known points are there to adjust them to the grid?

you do differential GPS. One needs to know that GPS primarily is a time signal plus the position of the satelite. You get that from several satelites. By the time elapsed from the satelite sending it to you receiving it you  know the distance to that satelite. Then you do simple triangulation of those satelites positions and distances to find out your actual position. Because of thats a lot of arithmetics which has to be done in high precision, GPSes use quiet a lot of battery. My Garmin Edge 705 lasts about 10 hours with GPS enabled, and if you put it into a place where it doesn't get any satelite (like with the bike into the cellar) it lasts several days.

Differential GPS works like that:

you put up a GPS receiver station that "knows" its place, so you just need to calculate the difference to what the GPS signal tells it, and send that correction over to the mobile client.

In cars this is done via FM-Radio; you can do that via amateur radio if you want to roll your own.

that way you also get a higher resolution then GPS would offer in first place, plus 'selected availability' (as the military used to call the obfuscation) is next to useless.

Sa Nov 06 2010 12:38:35 EDT von IGnatius T Foobar @ Uncensored Betreff: Re:

Heh.  That's about the sum of it.  :)

Oddly enough, I was thinking about something like that a few days ago.  A real breakthrough would be to develop a way to directly convert the energy stored in one's body to electricity, for powering cell phones and computers and such.  Most of us are carrying around a bunch of extra stored energy that we don't really want.

(Yeah I know, hand cranked generators etc. etc.  I'm talking about a way to do it at the molecular level without all that.)

btw, from the Steven Chu article in politics & propaganda:

Chu's talk spans environmental history, deep-water drilling and energy efficiency. Explaining why electric car batteries are large and heavy, he uses a common measurement of energy and notes that a lithium ion battery stores 0.54 megajoules per kilogram. Body fat has 38 megajoules per kilogram, and kerosene has 43.

quiet a number, right?

so we should run our cars on body fat. That would be great.

oh wait, that's called a bicycle :)

now these do have snow:

http://arcticglass.blogspot.com/2010/11/embracing-cold.html

plus cycling with the MTB seems to be partialy possible.

like the muff he has at the handle bar.

Unacceptable!  We need a way to convert body fat directly to electricity without using muscles/generators.  I want a USB connector on my belly that I can use to run a laptop or a phone, and if the stored supply of energy really does start to run low I want to be able to eat a Big Mac to charge it.

you all be assimilated.

Thu Nov 25 2010 09:26:36 AM EST from IGnatius T Foobar @ Uncensored Subject: Re:

Unacceptable!  We need a way to convert body fat directly to electricity without using muscles/generators.  I want a USB connector on my belly that I can use to run a laptop or a phone, and if the stored supply of energy really does start to run low I want to be able to eat a Big Mac to charge it.

I like this plan, you're the geek, invent it please.

I'm willing to beta test.

Geez..here the snow is almost gone.  It's supposed to RAIN on Monday.  The Farmers Almanac has some 'splaining to do.  They said this winter was supposed to be colder than normal.

finaly it feels good to ride the SUV again.

yes, i'm talking about that GHOST alloy fixed tail thing with the big bad magura breaks attached to it and the two nasty 26" schwalbe nobby tires.

no skidding, no danger of losing track even in some muddy snow.

the feeling to ride on glue compared to the roadbike is gone. Riding slower is acceptable, since most cars do also.

oh, and finaly riding with a loaded airZound again.

overdid it with 'clothes to warm yesterday'

*chill*