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Index of Subjects -------------------------------1256044124 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit As Chris said, the degrading of the GPS position was very much a US policy, apparently primarily to degrade targeting information. The way major manufacturers got around the problem was by marketing Differential GPS. Receivers in significant navigation locations, Chebucto Head for example, received the GPS signal, compared it to the actual position of the receiver and transmitted the correction to shipborne receivers on a frequency of around 300khz. Prior to that, while the absolute accuracy of GPS was superior to Loran, the relative accuracy with Loran was very high. In other words, if you put something in the water and noted the Loran reading, it would still be very close to the same reading when you came back, assuming of course it was anchored. Loran errors can be quite large, but are generally constant. Peter Stow (ancient sea captain} Hubbards -------------------------------1256044124 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content=3D"text/html; charset=3DUS-ASCII" http-equiv=3DContent-Type> <META name=3DGENERATOR content=3D"MSHTML 8.00.6001.18828"></HEAD> <BODY style=3D"FONT-FAMILY: Arial; COLOR: #000000; FONT-SIZE: 10pt" id=3Dr= ole_body=20 bottomMargin=3D7 leftMargin=3D7 rightMargin=3D7 topMargin=3D7><FONT id=3Dr= ole_document=20 color=3D#000000 size=3D2 face=3DArial> <DIV><FONT size=3D3>As Chris said, the degrading of the GPS position was= very much=20 a US policy, apparently primarily to degrade targeting information.= The=20 way major manufacturers got around the problem was by marketing Differenti= al=20 GPS. Receivers in significant navigation locations, Chebucto Head for exam= ple,=20 received the GPS signal, compared it to the actual position of the receive= r and=20 transmitted the correction to shipborne receivers on a frequency of=20 around</FONT></DIV> <DIV><FONT size=3D3>300khz. Prior to that, while the absolute accuracy of= GPS was=20 superior to Loran, the relative accuracy with Loran was very high. In= other=20 words, if you put something in the water and noted the Loran reading, it= would=20 still be very close to the same reading when you came back, assuming of co= urse=20 it was anchored. Loran errors can be quite large, but are generally=20 constant.</FONT></DIV> <DIV><FONT size=3D3></FONT> </DIV> <DIV><FONT size=3D3>Peter Stow</FONT></DIV> <DIV><FONT size=3D3>(ancient sea captain}</FONT> </DIV> <DIV><FONT size=3D3>Hubbards</FONT></DIV></FONT></BODY></HTML> -------------------------------1256044124--
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