NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dip-meter again
From: Richard B. Langley
Date: 2012 Apr 12, 08:58 -0300
From: Richard B. Langley
Date: 2012 Apr 12, 08:58 -0300
Is this the photo? http://www.gpsworld.com/gnss-system/gps-modernization/the-origins-gps-part-2-fighting-survive-10010 -- Richard On 11-Apr-12, at 5:54 PM, Lu Abel wrote: > If you read the history of GPS, soon after Sputnik's launch American > scientists figured one could get positional data (maybe only a line- > of-position, not a fix) from the Doppler shift in a satellite's > signals. This resulted in a very hush-hush project that resulted > in the Transit system. Multiple US defense projects then looked > for a next-generation follow-up. Fortunately (at least for the > modern world) the projects were merged with the best ideas from each > being selected as the projects consolidated and moved forward. One > specific I remember is that one of the projects proposed that the > receivers contain an atomic clock! For 1960s or early 1970s > technology, not unreasonable -- we had not seen the dramatic effects > of shrinking semiconductor technology. Fortunately, that got > changed. There's a wonderful picture of a soldier wearing a full > backpack with a large antenna sticking out of it. It's a single- > channel GPS receiver! (wish I could find a copy to attach, but I > can't) > > From: Alexandre E Eremenko> To: NavList@fer3.com > Sent: Tuesday, April 10, 2012 11:14 AM > Subject: [NavList] Re: Dip-meter again > > > Richard, > Thanks. > Do you know how accurate it was? > > > The first TRANSIT satellite was launched in 1961. The system was > > declared operational in 1964 and became classified. In 1967 it was > > declassified and became available for civilian use. > > Alex. > > > > > > ----------------------------------------------------------------------------- | Richard B. Langley E-mail: lang@unb.ca | | Geodetic Research Laboratory Web: http://www.unb.ca/GGE/ | | Dept. of Geodesy and Geomatics Engineering Phone: +1 506 453-5142 | | University of New Brunswick Fax: +1 506 453-4943 | | Fredericton, N.B., Canada E3B 5A3 | | Fredericton? Where's that? See: http:// www.fredericton.ca/ | -----------------------------------------------------------------------------