Figure 3-13.Range-marker generator.
The range step is often used to determine target range on an A-scope presentation. The appearance of
a range step on an A-scope is illustrated in figure 3-14.
Figure 3-14.Range-step presentation.
View A of figure 3-15 is a block diagram of a simple range-step generator consisting of a sawtooth
generator, a negative clipper, a range potentiometer, and a limiting amplifier. The position of the range
step along the indicator's time base is controlled by the range potentiometer. When the range step
coincides with the leading edge of a target's echo pulse, the range can be read directly from a calibrated
readout associated with the potentiometer.