A brief history of GPS
Fri, 08/10/2012 - 8:49am
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     13 years
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It all started with Sputnik. What seemed at the time like a major defeat in the Cold War, turned out to be the catalyst for one of the most important technologies of the 20th century, and maybe the 21st.
It was October 4th, 1957. Scientists at MIT noticed that the frequency of the radio signals transmitted by the small Russian satellite increased as it approached and decreased as it moved away.
dopler effect
early redar used the same effect to remove clouds and slow moving objects from the data to display only faster moving things such as an airplane This came before 1957
260, 295W, 1490T,2455LMT
Iridium
Anyone remember the Iridium phones?
NUVI40 Kingsport TN
Doppler Effect
The change in frequency caused by movement is known as the Doppler effect. First published in 1842.
http://en.wikipedia.org/wiki/Doppler_effect
Jim F.
National Guard
Anyone remember the Iridium phones?
We have a few at my guard unit that we maintain
Streetpilot C340 Nuvi 2595 LMT
Technology is amazing.
Technology is amazing.
http://www.poi-factory.com/node/21626 - red light cameras do not work
wow
Anyone remember the Iridium phones?
We have a few at my guard unit that we maintain
Shocked they still work.
Do you know how they got that name?
NUVI40 Kingsport TN
Why?
Shocked they still work.
http://www.iridium.com -- they have a lot to offer.
*Keith* MacBook Pro *wifi iPad(2012) w/BadElf GPS & iPhone6 + Navigon*
No idea
Anyone remember the Iridium phones?
We have a few at my guard unit that we maintain
Shocked they still work.
Do you know how they got that name?
No idea where it came from actually.
Streetpilot C340 Nuvi 2595 LMT
The story is...
Anyone remember the Iridium phones?
We have a few at my guard unit that we maintain
Shocked they still work.
Do you know how they got that name?
No idea where it came from actually.
Anecdotally, the story goes that they were originally going to send up 77 satellites. Iridium has an atomic number of 77.
However, they were only able to send up 66. They didn't want to change their name to Dysprosium.
NUVI40 Kingsport TN
I remember commercials for
I remember commercials for the Iridium phones in the late 90's. I think Alec Baldwin did one of the voice overs.
Iridium (satellite phones)
The sailing community is a big market for satelite phones. Particularly those that circumnavigate the globe or travel to remote areas. It is one of the only ways to communicate (I think they use short wave radio too, but I don't know too much about that).
Jim F.
And Glonoss+GPS should be on your next unit's feature list
Being an owner of a Nuvi1450, Oregon450 & an eTrex30, let me simply say that Glonoss + GPS (as implemented on the eTrex30) does matter in handheld hiking unit! For tracking/hiking (U.S.)GPS alone is obsolete and units so equipped should be heavily discounted!
https://en.wikipedia.org/wiki/GLONASS
GPS Satellite Info
Current satellites
ftp://tycho.usno.navy.mil/pub/gps/gpsb2.txt
Some additional GPS info can be found here.
http://tycho.usno.navy.mil/gps.html
GPS Fact Sheet
http://www.navsea.navy.mil/nswc/dahlgren/ET/GPS/GPS.pdf
Shortwave
The sailing community is a big market for satelite phones. Particularly those that circumnavigate the globe or travel to remote areas. It is one of the only ways to communicate (I think they use short wave radio too, but I don't know too much about that).
14.300!
KD5XB in DM84
Thanks Boxcar
phlatlander