User`s manual

29
To draw the new filter curve, you will need to carefully click the mouse cursor on points within
the filter display area which correspond to the desired attenuations at the desired
frequencies.
While the mouse click button is held down, the Freq and Atten readouts will be updated as
the mouse is moved; you can use this feature to place points in the filter curve at exact
frequencies and attenuations. When the mouse click button is released, a line segment will
be drawn from the last defined point on the curve to the current mouse cursor position.
For this example, placing points at precise frequencies and attenuations is not required; draw
the curve approximately as shown in the figure below using mouse clicks.
Note that the very first click always sets the 0 Hz attenuation starting point.
Hint: To advance the frequency a single step move the cursor to the left ofthe last frequency
position and click to mouse. The curve will advanced the smallest step at the specified
attenuation.
Figure 7-19: Spectral Graphic Draw in Progress
5. Complete drawing the filter curve as shown below by drawing points all the way to the right
edge of the filter display area.
Figure 7-20: Completed Spectral Graphic Draw
When you have drawn the last point (must be at or beyond the right edge of the filter display
area), the the Spectral Graphic control window will return to normal appearance.
6. Suppose you decide that you would like to remove the "dip" which occurs in the filter curve at
approximately 3000 Hz in the figure, above. Click on Edit to bring up the following display:
Figure 7-21: Spectral Graphic Edit Window