We present electrical LC resonators with superconducting coils of 3.5 H inductance, operating in the frequency range 250-1500 Hz with quality factors up to Q =1.6 x 106. The coil has a reduced, < 100 pF, stray capacitance and is housed in a superconducting case. Measurement are made with a low coupling SQUID readout. We briefly discuss some possible applications of the device.
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