This seems to be an easy task, just connect your multimeter and see what you get.
...or is it a little bit more tricky than that?
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What would you consider being the "standard" method to measure the dreaded noise and ripple from our beloved power supplies?
I cant seem to find very much useful info on the www (lmgtfy please
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)
Of course i watched #594 (thanks Dave) but i want more!
but i want more!
My setup today:
I use a scope, isolated from mains.
Measure with 20MHz filter, averaging 1000 times
and AC-coupled (duh..) 1Mohm input.
Using 1m of RG58 coax (~82pF), shortest possible leads to terminal and a BNC connector to the scope.
- Should i use a capacitive load at the scope terminal, around 10µF? (saw that in a datasheet somewhere)
S Should a scrap my coax and use a scope probe, but then i will have a long ground wire, i can use a BNC adapter on the probe and then a BNC-banana adapter...
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- Should i do my readings at the minimum, middle and maximum voltage if a lab psu or is it always at maximum voltage? (the ripple and noise can vary greatly over the range)
- What should i consider when i measuring the PSU under load, there is no dutycycle to take in consideration on a lab PSU so should a max it out?
Thoughts and facts are welcome, and by the way, a happy new year!
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