Well my experience with identifying Electrolytic capacitors be they
conventional or
Tantalum is that if you see two negative looking bars on both sides start
worrying!

Sure, Manufacturers seems to take pride in doing their own thing, but if I
found a cap with nothing on one side, and a stipe on the other, given that
the East decided to change the
standard colour code of mains wiring from RED/BLACK/GREEN to
BLUE/BROWN/GREEN, I would assume
the stripe meant POSITIVE. Can you see the logic in that?

As Russell said, use a meter and measure the cap. Its easy to tell the
polarity this way.

And to wander off topic, this sheep import tax scenario sounds like a
payback for
Aussie giving the US of A a hard time over the Olympics and Marching Bands
to me?
Could this be so?

Cheers .. Bob


> -----Original Message-----
> From: pic micro controller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Russell McMahon
> Sent: 9 July 1999 08:51
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: Radio Shack, electrolytic caps, polarity, poor label, dumb
> tech
>
>
> >At least we don't have weird accents like those aussies and
> sheep-chasing
> >new zealanders. <G>
> >
> >Andy
>
> That should be "New Zealanders", please.
>
> Note that we are good at what we are good at -
>
> 1.     All English is migrating towards being spoken as she is spoken
> here (even genuine Brit version, to their horror).
>
> 2.    The mighty US of A is so scared of our free market unsubsidised
> sheep farming efficiencies that they have slapped a 9% import tax
> (called something else) on our lamb imports to protect the poor
> inefficient uncompetitive  US sheep farming industry - sounds like
> sheep-belly politics to me :-).
>
> 3.    TO KEEP THIS ON TOPIC :-)
>
> A nice trick for checking electro cap (metal can version only)
> polarity in circuit that I have not seen mentioned elsewhere (I
> should post this separately perhaps?)
>
> - Ground negative meter probe
> - Operate circuit
> - Measure voltage on can of working electrolytics.
>
> Properly polarised caps will typically show a voltage of from about
> 0.1 to 0.5 volts. Reverse biased caps will have a can potential much
> closer to supply. ie the can is not at but is NEAR the potential of
> the true negative terminal. For a reversed cap in the 10uF - 1000uF
> range on a 5 volt supply the can is typically at 2 or 3 volts but
> anything over about 0.5 is suspect.
>
>
> regards
>
>             Russell McMahon
>
>
>
>
>
>
> >==================================================================
> >Andy Kunz               Life is what we do to prepare for Eternity
> >------------------------------------------------------------------
> >andy@rc-hydros.com      http://www.rc-hydros.com     - Race Boats
> >andy@montanadesign.com  http://www.montanadesign.com - Electronics
> >==================================================================
> >
>