non polarised capacitors

[M0BSW]

Hi, I need a non polarised electrolytic capacitor, and I'm in a bit of a pinch, I remember that there is a way of wiring two polarised caps to make a no polarised cap, but I can't for the life of me remember how to do it , can anyone help.

[SeanB]

Back to back in series same value.

[M0BSW]

Back to back in series same value.

It is just to try something out , before buying a non polarised cap, as the thought of one of them degrading wouldn't be good.

[The Electrician]

What's the application?  Will the voltage across the NP cap have a substantial DC component for any length of time?

[M0BSW]

Back to back in series same value.

It is just to try something out , before buying a non polarised cap, as the thought of one of them degrading wouldn't be good.

I don't think so, I'm using them as a part of a noise filter at the speaker end on a receiver.  the output is around 3 watts into a 8ohm speaker. This is the basic circuit.

[Mr Smiley]

From a pdf document i got some from where i can't rememter 

"
If two, same-value, aluminum electrolytic capacitors are
connected in series, back-to-back with the positive termi-
nals or the negative terminals connected, the resulting sin-
gle capacitor is a non-polar capacitor with half the capaci-
tance to either of the original pair. The two capacitors recti-
fy the applied voltage and act as if they had been bypassed
by diodes. When voltage is applied, the correct-polarity
capacitor gets the full voltage.
"