A professional who verifies speed of spindles and travelers on yarn twisting and spinning frames, using stroboscope, and makes minor adjustments. Responsibilities include:

• Turns knob to adjust stroboscope setting to spindle speed specifications.
• Directs stroboscope light beam onto revolving bobbin.
• Observes bobbin and traveler to detect illusion of movement indicating variance between spindle speed and speed setting of stroboscope.
• Turns knob to synchronize stroboscope light oscillations with speed of malfunctioning spindle, and records incorrect spindle speed as shown on stroboscope r.p.m.
• dial.
• Makes adjustments, such as tightening screws and removing waste from travelers.
• Notifies machine fixer of machines requiring repairs, such as replacement of spindles and travelers.
• May use twist-test machine to determine twist (number of turns per inch) in yarn to verify accuracy of machine setup.
• May test yarn tension, using tensiometer.