Questions

RADAR - RAdio Detection And Ranging.

A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. 

Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain.

Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the object's location and speed.

The Micro Processor enters into Halt-State and the buses are tri-stated. 

RST 4.5 is called as TRAP.

In each circle, starting at the  top left segment ,numbers increase, as you move clockwise,by 2 for the upper left circle,3 for the upper right, 4 for the lower right and 5 for the lower left

The sheet number on the map is found in bold print in both the upper right and lower left areas of the margin.