For a record player to reproduce music properly, it must play the record at the correct speed. There are three standards for record player speed, measured in RPMs (revolutions per minute) -- 33 RPM, 45 RPM, and 78 RPM. Some record players (or turntables) have a strobe light mechanism that lets you check the speed of the player and calibrate it. Some models do not. If you have a record player or turntable that doesn't have a strobe light for calibration, and you're uncertain that it is playing at the correct speed, there's a simple way to measure the speed that the platter of the record player is moving. It only takes a few minutes to do, and the simplest of tools.
Instructions
1. Take any records off of the turntable. Put a small piece of masking tape (about 1/2 inch) on the edge of the platter.
2. Set a stopwatch or timer to count down 1 minute. You'll need a timer with an alarm, or have have someone assist you in timing one minute.
3. Turn on the turntable and let it reach full speed. When you're ready start the timer or have your assistant tell you when to begin. At the mark, watch the platter rotate, and count the number of times the mark you've made passes by.
4. When the timer stops, or your assistant tells you to stop, quit counting. The number you've counted is the speed of the turntable, measured in RPMs. To be certain about your measurement, repeat the counting process two or three more times.
Tags: record player, correct speed, have strobe, have strobe light, measured RPMs
