Digital StroboscopeUsed in motion studies in classrooms, physics and Q. C. labs. Convenient for non contact measurement of running machinery in factories and elsewhere since, unlike tachometers, stroboscopes require no special reflective tapes. Powerful xenon lamp. The high 4 digit LED is easy to read in both light and dark environments. Microprocessor circuit with a crystal time base insures high accuracy over a wide range and does not require recalibration. Built in