Milestone-Proposal:LORAN: Difference between revisions
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Today's loran operates on one of several frequencies between1700 and 2000 kHz. It enjoys propagation characteristics determined primarily by soil conductivity and ionospheric conditions. Both ground wave and sky waves can be used to provide coverage over an extensive area with few stations. Usually. stations of a pairs are located 200 to 400 miles or more. At one time, several station pairs were separated by 1000 to 1400 miles apart. Transmitters now in use radiate about 100kw and give a ground-wave range oversea water of about 700 nautical miles in the daytime. The day time range over land is seldom more than 250 miles even for high-flying aircraft and is scarcely 100miles at the surface of the earth. At night the ground-wave range oversea water is reduced to about 500 miles by the increase in atmospheric noise, but sky waves, which are almost completely absorbed by day,become effective and increase the reliable night range to about 1400miles. Generally,, a number of stations are located so as to form a chain, with all but the end station in the group being double pulsing. In most parts of the world,, signaals can be received from at least two pairs of stations making it possible to determine a fix using loran alone. | Today's loran operates on one of several frequencies between1700 and 2000 kHz. It enjoys propagation characteristics determined primarily by soil conductivity and ionospheric conditions. Both ground wave and sky waves can be used to provide coverage over an extensive area with few stations. Usually. stations of a pairs are located 200 to 400 miles or more. At one time, several station pairs were separated by 1000 to 1400 miles apart. Transmitters now in use radiate about 100kw and give a ground-wave range oversea water of about 700 nautical miles in the daytime. The day time range over land is seldom more than 250 miles even for high-flying aircraft and is scarcely 100miles at the surface of the earth. At night the ground-wave range oversea water is reduced to about 500 miles by the increase in atmospheric noise, but sky waves, which are almost completely absorbed by day,become effective and increase the reliable night range to about 1400miles. Generally,, a number of stations are located so as to form a chain, with all but the end station in the group being double pulsing. In most parts of the world,, signaals can be received from at least two pairs of stations making it possible to determine a fix using loran alone. | ||
A BRIEF HISTORY | A BRIEF HISTORY | ||
The name loran is derived from long-range navigation, a name given by Lawrence M. Harding, a career officer of the United States Coast Guard (USGC). Harding is one of the loran pioneers not | The name loran is derived from long-range navigation, a name given by Lawrence M. Harding, a career officer of the United States Coast Guard (USGC). Harding is one of the loran pioneers we should not forget. Beginning in 1943, USCG played a key role in getting some twenty-five loran transmitter stations up and running in the Pacific. Pierce gives credit to the USCG for loran stations in Iwo Jima and Okinawa, erected closely upon the heels of the invading forces. Other loran stations in the Pacific helped guide the Air Force in its bombing campaign. Until quite recently, USGC crews have been manning loran stations in this part of the world for over 60 years. The loran system in the United States was shut-down by the government on 8 February 2010. The nominator witnessed this great event, planting the seed for this milestone nomination. | ||
But other individuals should be mentioned: | |||
1941 - Melville Eastman of the Microwave Committee: first leader of the Rad Lab group or division assigned to develop radio navigation. In the spring of 1941, a small the founder of General Radio Corporation of Cambridge, was organized under the newly formed Radiation Laboratory of the Massachusetts Institute of Technology, from which it drew two or three key personnel, while other were recruited from outside sources. Further research and investigations were undertaken and soon indicated that changes in the basic design were necessary.. | 1941 - Melville Eastman of the Microwave Committee: first leader of the Rad Lab group or division assigned to develop radio navigation. In the spring of 1941, a small the founder of General Radio Corporation of Cambridge, was organized under the newly formed Radiation Laboratory of the Massachusetts Institute of Technology, from which it drew two or three key personnel, while other were recruited from outside sources. Further research and investigations were undertaken and soon indicated that changes in the basic design were necessary.. | ||
radio frequency, patterns, wave reflection | radio frequency, patterns, wave reflection | ||
When a grande long-lived engineered system like LORAN, .. this nomination milestone gives credit to those persons that worked on the so-called Project 3 or C | When a grande long-lived engineered system like LORAN, .. this nomination milestone gives credit to those persons that worked on the so-called Project 3 or C | ||
. The USCG had a permanent office working on this project. One person in particular that deserves mention is Coast Guard Lt. Cmdr. L.M. Harding who provided supervision and direction for the Pacific Loran ... | . The USCG had a permanent office working on this project. One person in particular that deserves mention is Coast Guard Lt. Cmdr. L.M. Harding who provided supervision and direction for the Pacific Loran ... | ||
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Among his many awards are a 1948 Presidential Certificate of Merit and the 1953 Morris Liebmann Prize of the Institute of Radio Engineers. | Among his many awards are a 1948 Presidential Certificate of Merit and the 1953 Morris Liebmann Prize of the Institute of Radio Engineers. | ||
JA Pierce was . . .???///// | JA Pierce was . . .???///// | ||
LORAN CITATION | LORAN CITATION | ||
JA Pierce | JA Pierce | ||
Revision as of 20:42, 10 December 2010
This Proposal has not been submitted and may only be edited by the original author.
Pierce Loran.pdf
Loran1.jpg .png
Loran_chart.png
This is a test
