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Mundorf Mcap Supreme outer foil?

I’m having a hard time determining the outer foil side of Mundorf 0,47 µF Mcap SUPREME Classic capacitors.

The trick with the oscilloscope (10 mV scale) doesn’t show any difference between connections and the 50 Hz. hum is hardly noticeable when touching the capacitor’s body.

I’m not sure what to do now. Leave it undetermined and just pick a side?

Regards, Gerrit
 

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The foil side should point towards the lowest impedance point. I know Mundorf EVO caps designate the short lead as the foil side. If you have a scope you could check a few ways that are mentioned in this BB but like Jon said it really makes little or no impact if you don't know what side of the cap is toward the lowest impedance point. LOL just had this conversation with myself last week..........called some ppl read some stuff thats what I came up with......not mission critical still if it can be done why not?
 
I want to use them for coupling and would like to do it the “preferred” way, using the outer foil side on the lowest impedance point. I will measure the lead lengths tomorrow, but I don’t remember any difference. At least I want to use the same orientation for both channels.

Regards, Gerrit
 
Hook up the scope to the cap, hold the body in one hand, and touch a lamp or another electrical appliance with the other. That way you capacitively couple the cap to the lamp (or other) and you should see a signal. I've never "measured" a cap that didn't show a difference.