How measure safely AC mains pollution noise

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I use REW5. But imho you should get any mains AC measurement probing 'technique' checked fully by a competent person before exposing yourself to risk of electrocution.

Technique implies a circuit diagram, safety equipment such as earth leakage switch, carefully selected parts, review of process and risks. I know it's a forum, and I know that some forums ban threads on AC mains work.
 
you can use any power analyzer, its input stage usually high impedance with mega ohms resistors.
today they were cheap from chinese.

attached is fluke43b, not this one, it has issues with fragile lcd, psu, battery, etc.
 

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My objectives are measuring the effectiveness of using 1) line filter and/or 2) isolating transformer on reduction of main noise. My set up for measuring AC main noise (not yet tested):

1. a differential probe (from EEVblog)
2. an Oscilloscope (a cheap Rigol)
3. an audio analyzer (RTX from a group buy in this forum)

A differential probe is used to avoid connecting the neutral line of DUT to the power ground of the scope directly. A scope is used to identify high frequency noise as audio anaylzer is usually limited in bandwidth. An anlyzer is used to plot the FFT of the AC mains noise (a Rigol scope can also do it but the resolution is limited when compared with an anlyzer). Here are my initial thought and I've just finished collecting these items. Hope I can start the measurement soon.
 
Any standards testing house will have a LISN and spectrum analyser for stock standard EMI conductance compliance, but there are also different LISNs to test over other frequency ranges than mandated. Standard analysers filter for peak and quasi peak levels. You may be able to find or loan old LISNs and analysers that are uncalibrated and have been replaced over the years.
 
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