Going "outside the box" a bit...
I'd be interested in a comparison between your results and trying a standard off-the-shelf IEC mains input filter - connect +ve and -ve to either live or neutral (doesn't matter which way round) and the case to GND.
The cheaper IEC filters are single stage, the more upmarket ones are two stage and provide great filtering at RF.
Your graphs show about 25dB reduction in noise up to 50kHz - these mains filters do at least that and obviously attenuate far more at higher frequencies... Note that some mains filters don't attenuate much up to 100kHz, but there is noise, and then there is noise (differential,common mode etc.)
The 3EMC1 3A single phase filter is a good example - 3EMC1 data sheet - there are many others... e.g. look at the TFK-3 graph in http://docs-europe.electrocomponents.co ... 02a7d7.pdf
Half the cost (if it works) and not boxed "magic". Using an IEC 60320 C14 inlet connector with included filter would be cheaper, but those tend to be single-stage filters...
Edit: More - http://www.audiomisc.co.uk/mains/filters1.html - rolling your own wouldn't be tricky... what about just passing the power leads several times through a ferrite core?
etc.
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- Paul Barker
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#17
We always used to make our own.
The cheapest source of basic EMI supressors are in dead microwaves and washing machines.
The cheapest source of basic EMI supressors are in dead microwaves and washing machines.
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#18
Electronics Goldmine selling good two-stage ones for only $2.50
http://www.goldmine-elec-products.com/p ... ber=G19096
Type STE8-3 from SAE Power Inc.
Data sheet here: http://www.saepower.com/pdf/emi-filter_catalog.pdf
At 150kHz, common mode 58dB down, differential 36dB down.
http://www.goldmine-elec-products.com/p ... ber=G19096
Type STE8-3 from SAE Power Inc.
Data sheet here: http://www.saepower.com/pdf/emi-filter_catalog.pdf
At 150kHz, common mode 58dB down, differential 36dB down.
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