another beginner

[Martin Czech]

> I am a bit confused about polarized capacitors, if they are in a circuit
> with alternating current, how is it that the polarity does not change and
> ruin the cap, is there something really obvious I'm missing?
> 
> Thanks in advance...

It is true that large dc revers polarity will kill the cap.
Ac is different, if the swing is low, no problems may occur.
I'm no cap expert, check out the unofficial archive for
the cap faq page.

Check out: http://www.evenfall.com/diy/archive/index.html

m.c.