AP 3302 Pt. 3
Section 1
CHAPTER 1
PULSE-MODULATED RADAR
If the spot always moves at the same rate, every inch of trace represents 5 miles of range. The range of any target which produces an echo can therefor be found simply by measuring the distance of its echo from the start of the trace. One fleeting echo would be of little value as a means of indicating a target. We therefore arrange for a continuous picture to be built up by sending out pulses in rapid suuession.
The echo paints are produced by converting the signals picked up by the receiver into short pulses of d.c. voltage which we apply to the Y-deflecting plates of the c.r.t. This pulls the spot upwards for the duration of each pulse (Fig 10c) Sometimes the echo is required to show up as a
