About Lock-In Amplifiers
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Stanford Research Systems phone: (408)744-9040 www.thinkSRS.com Lock-in amplifiers are used to detect and measure very small AC signalsall the way down to a few nanovolts. Accurate measurements may be made even when the small signal is obscured by noise sources many thousands of times larger. Lock-in amplifiers use a technique known as phase-sensitive detection to single out the component of the signal at a specific reference frequency and phase. Noise signals, at frequencies other than the reference frequency, are rejected and do not affect the measurement.
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About Lock-In Amplifiers
Stanford Research Systems phone: (408)744-9040 www.thinkSRS.com Lock-in amplifiers are used to detect and measure very small AC signalsall the way down to a few nanovolts. Accurate measurements may be made even when the small signal is obscured by noise sources many thousands of times larger. Lock-in amplifiers use a technique known as phase-sensitive detection to single out the component of t...
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Method in which lock-in detectors process signals from standard ac susceptometers, particularly in the detection of higher harmonics, is analyzed in details. The exact formulas have been derived and checked experimentally by measurements on soft ferromagnetic sample, using several available lock-in amplifiers. The reasons why the proper phase adjustment has to be implemented in the protocol of ...
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