Abstract: A magnetostrictive position or elongation sensor of the type in which an elongated magnetorestrictive waveguide is influenced by a magnetic field from a moving magnet has a Villary type transformer at one end and a hermetically sealed housing containing the signal processing circuitry on a plurality of circuit boards. The signal processor can switch the sensor into a programmable mode in which a diagnostic output is obtained recognizing the magnet, the presence of the sensor in the programming mode and voltage values.