TA 50 T 2 Map Reading Polar Coordinates

NORMTRONICS

AUTHOR: SFC NORMAN M. VANCE

MAP
READING
Determine Polar Coordinates

Maptech® USGS Topographic Series™, ©Maptech®, Inc. 978-933-3000,

www.maptech.com/topo Copyright 2001 Maptech,

Polar Coordinates
Plot Azimuth from a known point.
Plot distance from the know point along the azimuth line.
The polar coordinate is at the end of the azimuth/distance line.

STEP 1. PLACE THE INDEX MARK OF THE PROTRACTOR AT THE
CENTER OF MASS ON THE POINT FROM WHICH YOU ARE
MEASURING.

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STEP 2. LOCATE THE DESIRED AZIMUTH ON THE PROTRACTOR
SCALE AND PLACE A DOT ON THE MAP AT THIS
AZIMUTH.

56

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EXAMPLE: 56 DEGREES

STEP 3. REMOVE THE PROTRACTOR AND CONNECT THE POINT
AND DOT WITH A STRAIGHT LINE.

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STEP 3. REMOVE THE PROTRACTOR AND CONNECT THE POINT
AND DOT WITH A STRAIGHT LINE.

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STEP 1. SELECT THE APPROPRIATE SCALE MEASUREMENT AND
PLACE A PAPER STRAIGHT EDGE ON THE SCALE.

EXAMPLE: DISTANCE IN METERS

STEP 2. DETERMINE THE DESIRED DISTANCE TO MEASURE FROM
THE SCALE AND MARK THE PAPER AT THIS DISTANCE
USING TICK MARKS.

EXAMPLE: 3400 METERS

STEP 3. ALIGN THE STRAIGHT EDGE WITH THE AZIMUTH LINE.
ENSURE THE FIRST TICK MARK IS CENTER MAST
ON THE KNOWN POINT.

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STEP 4. PLACE A DOT ON THE MAP AT THE SECOND TICK MARK
FROM THE STRAIGHT EDGE ON THE MAP.

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THE POSITION OF THE SECOND TICK MARK
IS THE POSITON OF THE UNKNOWN POINT.

REMOVE THE STRAIGHT EDGE AND DETERMINE THE GRID
COORDINATE TO THE SECOND POINT.

EG158821

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