A simple liquid level indicator for a metal dewar has been constructed withthe use of superconducting elemental Ta and Nb-Ti alloy as well as carbonresistor. Electrical and superconducting properties, repeatability, sensitivity,and a practical operation of the indicator have been investigated at 78°K and4.2°K. The hysteresis or instability effect of the resistance for Nb-Ti wirewas found at the magnetic field of 17 kG. Evaporation rate of liquid heliumcan be estimated in the dewar with a few indicators.
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