Platter Speed Check

Idle
Not measuring
0.00 rpm
±0.00 %

Wobble
–
Averaged
0 s
Zero offset
none
How to calibrate
  1. Open this page on your phone and tap Start sensor.
  2. Lay the phone flat and still (e.g. on the stopped platter) and tap Zero offset. Hold still for 3 seconds. This removes the gyroscope's built-in drift.
  3. Place the phone flat in the middle of the platter, screen up. Where it sits doesn't matter, only that it doesn't slide.
  4. Start the turntable and wait about 10 seconds for it to settle.
  5. Adjust the speed pot or pitch control until the deviation reads near 0.0 %. Use Restart average after each adjustment.
  6. Finish with the 30 s window to confirm.

Phone gyroscopes are typically accurate to about ±0.5–1 %, so treat this as a good first pass. For the last tenth of a percent, confirm with a strobe disc. A heavy phone can slow a light belt-drive platter slightly, so a light phone gives the truest reading.