Get the latest tech news
Show HN: Racketmeter – Measure Badminton String Tension Using Sound Frequency
Racketmeter is the easiest way to measure badminton racket string tension using the mic on your device. No more expensive equipment needed. Just use your phone or computer to measure your racket tension.
Instructions Click "Start Measuring" button. Then firmly hit the strings 4-5 times against the heel of your hands to get a measurement. Accurately measure badminton racket string tension using mic of your device
Or read this on Hacker News