Longitudinal Magnetic Deviation

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Houston

SatelliteGuys Family
Original poster
Mar 28, 2006
113
0
Houston, Tx USA
I’ve looked at several “maps”, with the MD lines on them, and find that it’s really hard to tell just where your location is on them. Does anyone know a url where they have a real clear map, and I can get a good location on it ?
 
Houston said:
I’ve looked at several “maps”, with the MD lines on them, and find that it’s really hard to tell just where your location is on them. Does anyone know a url where they have a real clear map, and I can get a good location on it ?


You really need the map or just to know the value for your location ?


Download SatFindr at


http://www.arachnoid.com/satfinder/SatFinder.exe


Houston, TX 77099
Latitude 29° 40.254'N Longitude 95° 35.196'W

Sat Name Sat Lng Az(t) Az(m) El Skew
-------------------------------------------------------------
*** Of Particular Interest ***

EchoStar 3 61.5W 126.2 121.9 39.3 -44.5
EchoStar 6 110.0W 207.4 203.1 52.0 23.6
EchoStar 8 110.0W 207.4 203.1 52.0 23.6
EchoStar 7 119.0W 221.2 216.9 46.9 34.9
EchoStar 5 119.0W 221.2 216.9 46.9 34.9
EchoStar 9/Telstar 13 121.0W 223.8 219.5 45.6 37.0
EchoStar 1 148.0W 249.1 244.9 24.1 54.3
EchoStar 2 148.0W 249.1 244.9 24.1 54.3
EchoStar 4 157.0W 254.9 250.6 16.2 57.0

DirecTV 3 81.8W 153.6 149.3 52.2 -22.7
DirecTV 2 100.8W 190.4 186.2 54.9 9.1
DirecTV 1R 100.8W 190.4 186.2 54.9 9.1
DirecTV 1 101.0W 190.8 186.5 54.9 9.4
DirecTV 4S 101.2W 191.2 186.9 54.9 9.7
DirecTV 6 109.8W 207.1 202.8 52.0 23.3
DirecTV 5 119.0W 221.2 216.9 46.9 34.9

*** All Satellites 61W - 160W ***

EchoStar 3 61.5W 126.2 121.9 39.3 -44.5
Rainbow 1 61.5W 126.2 121.9 39.3 -44.5
Brasilsat A2 (incl. 5.8 deg) 63.0W 127.8 123.5 40.5 -43.4
Brasilsat B2 65.0W 129.9 125.7 42.0 -41.8
Brasilsat B1 70.0W 136.0 131.7 45.5 -37.2
Nahuel 1 71.8W 138.3 134.0 46.7 -35.3
AMC 6 72.0W 138.6 134.3 46.8 -35.1
Galaxy 12 74.0W 141.4 137.1 48.1 -32.9
SBS 6 74.0W 141.4 137.1 48.1 -32.9
GOES 12 75.0W 142.8 138.5 48.7 -31.7
AMC 5 79.0W 149.0 144.7 50.9 -26.6
DirecTV 3 81.8W 153.6 149.3 52.2 -22.7
Nimiq 2 82.0W 154.0 149.7 52.3 -22.4
Brasilsat B3 84.0W 157.5 153.2 53.1 -19.4
XM Roll 85.0W 159.3 155.0 53.5 -17.9
AMC 9 85.0W 159.3 155.0 53.5 -17.9
AMC 3 87.0W 163.0 158.7 54.1 -14.7
Galaxy 9 91.0W 170.8 166.5 55.0 -8.0
Galaxy 11 91.0W 170.8 166.5 55.0 -8.0
Nimiq 1 91.0W 170.8 166.5 55.0 -8.0
Brasilsat B4 92.0W 172.8 168.5 55.2 -6.3
Telstar 6 93.0W 174.8 170.5 55.3 -4.5
Galaxy 8I (incl. 1.0 deg) 95.0W 178.8 174.5 55.4 -1.0
Galaxy 3C 95.0W 178.8 174.5 55.4 -1.0
Telstar 5 97.0W 182.9 178.6 55.4 2.5
Inmarsat 2 f2 (incl. 1.7 deg) 98.0W 184.9 180.6 55.3 4.2
Galaxy 4R 99.0W 186.9 182.6 55.2 6.0
DirecTV 2 100.8W 190.4 186.2 54.9 9.1
DirecTV 1R 100.8W 190.4 186.2 54.9 9.1
AMC 4 101.0W 190.8 186.5 54.9 9.4
DirecTV 1 101.0W 190.8 186.5 54.9 9.4
AMSC 1 101.1W 191.0 186.7 54.9 9.6
DirecTV 4S 101.2W 191.2 186.9 54.9 9.7
AMC 1 103.0W 194.7 190.4 54.5 12.8
Solidaridad 1 (incl. 2.8 deg) 103.5W 195.7 191.4 54.3 13.6
AMC 2 105.0W 198.5 194.2 53.9 16.0
G-Star 3 (incl. 11.5 deg) 105.0W 198.5 194.2 53.9 16.0
G-Star 1 (incl. 6.0 deg) 105.0W 198.5 194.2 53.9 16.0
MSAT 1 106.5W 201.3 197.0 53.4 18.4
Anik F1 107.3W 202.7 198.4 53.1 19.6
Anik E1 109.2W 206.1 201.8 52.3 22.4
DirecTV 6 109.8W 207.1 202.8 52.0 23.3
EchoStar 6 110.0W 207.4 203.1 52.0 23.6
EchoStar 8 110.0W 207.4 203.1 52.0 23.6
Anik E2R 111.1W 209.3 205.0 51.4 25.1
Solidaridad 2 113.0W 212.4 208.1 50.5 27.7
Morelos 2 (incl. 4.4 deg) 114.9W 215.3 211.0 49.4 30.1
XM Rock 115.0W 215.4 211.2 49.4 30.3
SatMex 5 116.8W 218.1 213.8 48.3 32.4
Anik E2 118.7W 220.8 216.5 47.1 34.6
DirecTV 5 119.0W 221.2 216.9 46.9 34.9
EchoStar 7 119.0W 221.2 216.9 46.9 34.9
EchoStar 5 119.0W 221.2 216.9 46.9 34.9
EchoStar 9/Telstar 13 121.0W 223.8 219.5 45.6 37.0
Galaxy 10R 123.0W 226.3 222.0 44.3 38.9
Galaxy 5 125.0W 228.7 224.4 42.8 40.8
Galaxy 12 125.0W 228.7 224.4 42.8 40.8
Galaxy 13 127.0W 231.0 226.7 41.3 42.5
Telstar 7 129.0W 233.1 228.8 39.8 44.0
Satcom C3 131.0W 235.2 230.9 38.3 45.5
Galaxy 1R 133.0W 237.1 232.8 36.7 46.8
Satcom C4 135.0W 238.9 234.6 35.1 48.1
GOES 10 135.5W 239.4 235.1 34.6 48.4
AMC 7 137.0W 240.7 236.4 33.4 49.3
AMC 8 139.0W 242.4 238.1 31.7 50.3
Inmarsat 2 f3 (incl. 1.9 deg) 142.0W 244.8 240.5 29.2 51.8
EchoStar 1 148.0W 249.1 244.9 24.1 54.3
EchoStar 2 148.0W 249.1 244.9 24.1 54.3
TDRS 9 (incl. 7.4 deg) 151.0W 251.2 246.9 21.5 55.3
TDRS 10 (incl. 6.2 deg) 151.0W 251.2 246.9 21.5 55.3
EchoStar 4 157.0W 254.9 250.6 16.2 57.0

Satellite Finder is (c) Copyright 2004, P. Lutus


Wyr
 
Declination – True, by Compass.

This is the procedure how to set the Magnetic Declination (MD) on a Compass and subsequently find True North/South.

First of all, you will have to “find/know” your MD, and the easiest way I know to do that, is to go to:

http://www.topozone.com/

Type in the City Name, and select the State, then when the new screen appears, click on your City which is located under the word “Place”. Sometimes there are multiple selections, so choose the one that is closer to the place you want the MD of.
Then, you will see the Map of the location. At this time, you should look to the Right Column, where you will find a selector for how you want the location displayed in Geographiametrics.

Select:
UTM,
Decimal: DD.DDD, (most popular)
Degrees & Decimal Minutes, DD.MM.MM or
Degrees/Minutes/Seconds.

IF you wish, you may enlarge the Map for a clearer view, and page up/dn/R/L, to select a specific area of the City to display. This will only change your MD about 0.1°, unless the City you’re locating in, is very large.

Once locating the specific area if chosen, look down on the lower right side of the page, and see your MD displayed in a small Avatar which has Arrows and Letters. The amount of MD is displayed in/with red, and "M =" is the value of the Magnetic Declination in Degrees, of the location highlighted on/in the Topo Map, indicated by a Red “+”.

Example: If you had typed in “Houston”, then selected “TX”, then when the next screen appeared, you clicked on Houston which was under the word “Place” on the next screen displayed. The MD you would see would be a (minus) – 4.06° (+/- 0.1°).
I offer this so you can check if you’re looking in the right place for the MD. Then back up to the first screen, and type in your location of interest.

Now, please refer to the Attachment. Houston13.jpg.

First, please notice the Adjustment Screw, identified in Text and the color line in yellow.

This rotates the “Arrow/Declination” plate, inside the Compass Ring, where you set the MD, for Plus or Minus.

If you need “Minus” MD, the Arrow Point should be moved to the RIGHT side of North, in the amount indicated on the Topo Map.

As you can see, the picture displays the Arrow to the Right of North, and though it’s hard to see, it IS set for – 4.06°.

If you live in the Eastern US, you would set the Arrow Point to the LEFT side of North, to get a “Plus” MD.

There is a scale on the Plate, and you would set the amount of MD directly at/under the mark which indicates “N/360°” on the Compass Ring.

Once this is set, use the Compass as it’s instructions state, by rotating the Frame to place the Cursor inside the Arrow, and True North/South is indicated by the “White” center line of the Compass.

Other Threads on this website concerning similar issues, may be found at:
http://www.satelliteguys.us/showthread.php?t=74011&highlight=True+South &
http://www.satelliteguys.us/showthread.php?p=546560#post546560 &
http://www.satelliteguys.us/showthread.php?t=55285 &
http://www.satelliteguys.us/showthread.php?t=61199
 

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