[en] A self-contained instrument for the measurement of magnetic fields is described which consists of a command module and a thermally stabilized Hall plate mounted in a probe. The command module contains the circuitry for the temperature stabilization and the current source for the probe, an analog-to-digital converter and a microprocessor-based control circuitry for the command of the measuring sequences. A read-only memory contains a calibration table for the relation between Hall voltage and magnetic field. The measured field strength can be directly displayed in units of induction (tesla). The teslameter is provided with a serial teletype input-output port for remote control. An addressing scheme allows up to 16 modules to be connected in parallel and to be controlled via a single teletype channel. This is especially useful if several teslameters are used in a complex measuring set-up. (Auth.)