Beurer PM 70 Operating Instructions Manual page 12

Measuring device of the Speedbox
Your HR monitor has all the functions to analyze the signals from the
Beurer Speedbox. A multidimensional measuring device is installed
in the Speedbox. This calculates the acceleration of your foot and
transmits this value to the HR monitor. The HR monitor displays the
distance covered and the speed, which is calculated from the accel-
eration and the time of each individual pace.
The following diagram shows the measured movements of feet over
two paces depending on the type of pace i.e. walking, jogging, run-
ning and sprinting.
Quelle: Dynastream Technology
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