Abstract: An equipment for the calibration of a temperature sensing device comprises an HF-induction coil capable of generating an alternating magnetic field which produces heat in the device to be calibrated. The actual temperature of the device is measured by a thermocouple attached directly to the surface of said device.

Abstract: An electrosurgical apparatus comprises a high frequency power generator, a high frequency transformer, a handpiece for mounting an electrode, and a connecting cable between the generator and the handpiece. In order to provide an automatic adaptation or adjustment so that the power delivered by the cutting electrode is continuously changed according to the cutting depth, the effective length of the connecting cable has been adapted to the output frequency of the generator so that the transfer characteristic of the cable provides a true ohmic transfer or reflection of the load at the electrode-end of the cable to the generator-end of the cable.

Abstract: Electric motors which are used for instance as driving motors for drilling and cutting implements incorporated in the handle of such implements, are subjected to strongly varying loads. This puts heavy demands to the regulation system of the motor. In a regulation system the signals which are provided by detectors (22) for currently sensing the position of the rotor relative to the stator, are supplied to a pulse generator (44, 46) which provides a pulse frequency being uniquely associated with the period of the varying detector signal. This pulse signal is supplied to a frequency-to-voltage converter (48) which provides an output signal being supplied to a diferential amplifier (50) as one input signal thereof, the other input signal being a reference DC voltage, and the output signal of the amplifier being supplied to a multiplier unit (40, 42) as one input signal thereof, the other input signal being said detector signal.