A digital voltmeter is shown to successfully capture the voltage decay
signal during eddy current decay (ECD) measurements at cryogenic temp
eratures on low-resistivity specimens. The use of a voltmeter simplifi
es ECD measurements, typically made using a digital oscilloscope. An a
dded benefit of using a voltmeter is that under certain circumstances,
measurement precision exceeds that which is normally obtained with a
preamplifier-digital oscilloscope combination. Results indicate that t
he best combination of instruments for capturing extremely weak signal
s (i.e., those with long exponential time constants) is a preamplifier
-voltmeter configuration. Results of a comparative study using a pream
plifier-digital oscilloscope configuration, a digital voltmeter alone
and a preamplifier-digital voltmeter arrangement are presented and dis
cussed.