Magnetic stirrer with no external moving parts.
This note describes a variable speed stirrer which is based upon a rotating magnetic field produced electronically. Digital circuitry is used to generate two stepped functions which approximate sine waves differing in phase by 90 degrees . The signals are amplified to drive sets of perpendicular coils such that a magnet situated between the coils rotates at the chosen speed.
Engel
P S
PS
Department of Chemistry, Rice University, Houston, TX 77001, USA.