An investigation was carried out on commercial Hall sensors used to me
asure the magnetic field of a superconducting magnet. Surprisingly, on
e of the GaAs Hall sensors, THS-119A, did not show Shubnikov-de Haas o
scillations under high field conditions. This sensor, which is availab
le as an electrical component for commercial circuits, was suitable fo
r measuring magnetic fields up to 25 T at temperatures from 1.5 to 300
K.