Abstract: The present invention relates to a milk-frothing unit comprising a frothing chamber, a suction portion which leads into the frothing chamber and an outflow which leads out of the frothing chamber, the frothing chamber, the suction portion and the outflow being configured such that milk can be suctioned in via the suction portion and guided into the frothing chamber and can be frothed up therein with gas and/or steam, in particular air and/or water vapour, which is supplied to this frothing chamber and in that the milk-froth mixture resulting from the frothing can be discharged out of the frothing chamber via the outflow, characterised in that the frothing chamber, the suction portion and the outflow are configured and disposed such that the milk to be suctioned in and the discharged milk-froth mixture can be guided in a circulation.

Abstract: A measuring cassette for checking magnetic head insertion distance and tape guide height in a magnetic tape cassette machine. A spring tongue in the cassette has at least one strain gauge on its surface to measure tongue bending, and is arranged to be deflected by insertion of the head into the cassette so as to sense the head surface or tape guide alignment with respect to the cassette.