User`s guide

34410A/11A/L4411A User’s Guide 121
Measurement Tutorial 4
susceptible to noise pickup than a low–impedance source. You can reduce the
high–frequency impedance of a source by placing a capacitor in parallel with
the multimeter's input terminals. You may have to experiment to determine
the correct capacitor value for your application.
Most extraneous noise is not correlated with the input signal. You can
determine the error as shown below.
Correlated noise, while rare, is especially detrimental. Correlated noise
always adds directly to the input signal. Measuring a low–level signal with the
same frequency as the local power line is a common situation that is prone to
this error.
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