A stroboscope is a flashing light source used to measure the speed of fast-moving objects. it produces the optical effect of stopping or slowing down an object to allow you to observe and analyze the objects motion. Figure 2-10 shows a typical stroboscope.

A stroboscope consists of a power switch, rpm control dial, range switch, calibration indicator light, calibration screws, combination adjustments, reflector lamp assembly, and other electrical accessories. For information about the functions of the components, consult the operators manual.

Before you use the stroboscope, be sure to read and follow the manufacturers operating instructions. The instrument commonly operates from a 120-volt, 60-Hz, alternating current supply. Any change in current frequency will affect the flashing speed and affect the stroboscopes accuracy for speed measurements. The stroboscope can be used to measure the speed and to observe the motion of rotating, reciprocating, or vibrating mechanisms. Never leave the stroboscope unattended while it is in use. Since the stroboscope makes a moving object appear to be standing still, someone could be seriously injured by the apparently stationary object.