User manual SEIKO TELEMETER

[. . . ] English TELEMETER (for models with telemeter scale on the dial) The telemeter can provide a rough indication of the distance to the source of light and sound. [. . . ] A flash of lightning reaches you almost immediately while the sound travels to you at a speed of 0. 33 km/second. The distance to the source of the light and sound can be calculated on the basis of this difference. The telemeter scale is so graduated that the sound travels at a speed of 1 km in 3 seconds. * *Under the condition of temperature of 20°C(68°F). HOW TO USE THE TELEMETER Before beginning, check that the stopwatch has been reset. English START (Flash of light) A 1 Press button A to start the stopwatch as soon as you see the light. STOP (Crash of thunder) 2 When you hear the sound, press button A to stop the stopwatch. 3 Read the telemeter scale CAUTION The telemeter provides only a rough indication of the distance to the place where lightning struck, and therefore, the indication cannot be used as the guideline to avoid the danger of lightning. It should also be noted that the speed of the sound differs depending on the temperature of the atmosphere where it travels. Approx. [. . . ] The telemeter scale can be used only when the measured time is less than 60 seconds. [. . . ]