Good and interesting article in Nuts and Bolts today

[satow]

I saw in the online version of Nuts and Bolts magazine an article about Finding the Outside Foil Lead on non-polarized capacitors and why it is important and how to check them. I thought it was well written and informative.
(Because the outside‑foil lead acts like a built‑in shield, knowing which end it is lets you place the capacitor in the circuit so it rejects noise instead of picking it up.)

 

[NTK]

Since the construction of a typical aluminum electrolytic capacitor is like this, the "outside" foil is not going to shield much of anything. Anyway, the function of a capacitor is to let high frequency through and block low frequency, noise in the RF range is not going to have much difficulty jumping across the two electrodes.

Picture source: https://en.wikipedia.org/wiki/Elect...f_non-solid_aluminium_electrolytic_capacitors

 

[satow]

Since the construction of a typical aluminum electrolytic capacitor is like this, the "outside" foil is not going to shield much of anything. Anyway, the function of a capacitor is to let high frequency through and block low frequency, noise in the RF range is not going to have much difficulty jumping across the two electrodes.

Picture source: https://en.wikipedia.org/wiki/Elect...f_non-solid_aluminium_electrolytic_capacitors

The article I read is available to the public. Source is here:

Finding the Outside Foil Lead

My methodology for identifying the outside foil lead on capacitors.

www.nutsvolts.com