High and low points between the two sites are as follows:

6-kilometer distance

150 meters

10-kilometer distance

132 meters

16-kilometer distance

144 meters

22-kilometer distance

120 meters

24-kilometer distance

150 meters

32-kilometer distance

156 meters

(2) You use the following steps to determine LOS:

(a) Step 1 - Determine the scales used from the contour map. In this exercise, this

is given in meters/kilometers.

(b) Step 2 - Identify the locations of the two points on the map. Draw a straight

line on the contour map between the two points. Measure the distance between the two points.

In this exercise, this is given to you (the distance from point A to point B is 40 kilometers).

(c) Step 3 - Determine the elevation at each site by analyzing the contour lines on

the map. This information is provided in this exercise.

(d) Step 4 - Mark the location of each site on the nonlinear graph paper. In this

exercise, the elevation at point A is given as 130 meters. The antenna height is given as 50

meters. To determine the total elevation at point A, add the elevation of site A and the elevation

height (130 plus 50 equals a total elevation of 180 meters). As indicated by the Step 4

instructions, mark the location of point A 180 meters above the 0-kilometer/0-mile elevation

scale on nonlinear graph paper (see Figure 2-5). Next, mark the location of point B on the

nonlinear graph paper. In this exercise, the elevation of point B is 136 meters. Since point B is

40 meters from point A, go to the 40-kilometer mark on the distance scale and then move up

vertically until the 186-meter elevation is reached. The location of point B is then marked (see

Figure 2-5).

(e) Step 5 - Draw a straight line between points A and B.

(f) Step 6 - Plot a profile of the terrain between the two sites. This step is

normally done by analyzing the contour lines between the two sites and determining the

significant high and low points intersected by the line. In this exercise, the information is

provided (plotted on the nonlinear graph paper in Figure 2-5). As previously stated, LOS exists

between the points A and B in this exercise.

(3) Figure 2-6, page 2-10, illustrates a non-LOS profile. An obstruction is present at

the 24-kilometer distance mark.

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