Re: power adapter... will it explode?

From: Robert Baer (bobbaer_at_earthlink.net)
Date: 09/23/04 

Date: Thu, 23 Sep 2004 08:22:32 GMT

DesignGuy wrote:
>
> "Jim Rex" <jimrex0@hotmail.com> wrote in message
> news:vPednfO1ttQjlc_cRVn-uA@rogers.com...
> > Hello,
> >
> > I have a pair of speakers that need a 13V and 2A DC power adapter or wall
> > wart. I lost its wall wart and found a wall wart for another device, which
> I
> > have no idea what its for.. it gives out 15V and 400mA DC.
> >
> > The power adapter I found said on its back that it must not be used with
> any
> > other device except..[some brand name]...
> >
> > Now, I used it with the pair of speakers and it worked!!! Now, i'm
> worrying
> > that this configuration could cause it to explode or something....
> >
> > Will it do any harm???
> >
> > P.S. (im cross posting to two newsgroups...)
>
> The speakers if they indeed need 2A to operate may damage the 400mA adapter.
> The extra 2 volts may or may nto harm the speakers, though likely not. Your
> best bet is to find a 12V 2A adapter since 13V is not a common value. Try
> Radio Shack or various online merchants such as DigiKey.

  It would be far better to use a 12V adaptor with that 2A rating.
  Most analog wall warts are unregulated, and they all put out more than
their rated voltage even at full rated load.
  In your case, the load may be more than its rated 400mA, which may be
saving your speaker system; the load may be large enough to drop the
voltage down to a safe level.

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