On Mar 9, 1:46*pm, "Michael*A.*Terrell"
wrote:
wrote in message

...
On Mar 9, 10:47 am, "Michael A. Terrell"
wrote:

Hello folks,

I am getting cheap these days, I am trying to cut corner by tripling the
capacitance in the capacitor, is this possible? I have heard that it's
possible. Some people have done it successfully. I am just wondering if
any of you smart dumbass can help.

If you weren't quite the ill-informed idiot that you are, you'd know
that the dielectric in an electrolytic capacitor is formed by the
electrolytic oxidation of the surface of the aluminium foil the forms
the plates of the capacitor.

If you reverse bias the capacitor you can reverse this process, making
the dielectric thinner ( and more likely to break down). Sadly, the
reverse process is unlikely to thin the oxide layer to exactly the
same extent at every point, so you run the risk of lowering the
breakdown voltage faster than you increase the capacitance.

Right, I agree with your blabla... except how do you convert existing
capacitors into a higher capacitance without starting from scratch as you
suggested?

Try reading what I wrote. If you reverse bias an existing capacitor -
apply a couple of volts of postive bias to the negative terminal and
ground the positive terminal - you should progressively convert some
of the insulating oxide layer back to aluminium. Measure the current
that is going through the capacitor while you are doing this and keep
it fairly low - as when you "reform" an electrolytic capacitor (which
doing exactly the opposite)

http://www.vcomp.co.uk/tech_tips/ref...eform_caps.htm

- how low depends on the capacitance of the capacitor you are fooling
around with.

A 33k resistor is probably as good as any to start with - if you screw
up the voltage until you've got say 30uA running through the capacitor
then leave it for a few minutes (watching to see whether the current
starts creeping up) then measure the capacitance of the capacitor
again to see if you've made any difference. Keep on extending the time
until you get bored, or do see a difference. If nothing much seems to
be happening, push up the voltage to get more current flowing.

I've never tried this - though I have reformed old electrolytic
capacitors - so I can't guarantee anything.

If you tried Pieter's approach you'd have a good chance of getting the
capacitor to spit out gobs of electrolyte, which creates an unpleasant
mess.

--
Bill Sloman, Nijmegen