[SPARCbook] buzzing noise from ac power supply

[E. Keith Howick, Jr.]

Actually this can work. Personally I'd prefer to find something that's buffering the
output with a transformer (DC-to-DC converter) rather than using a rectifier or bridge
to simply step the voltage down. Make sure you find something that produces *exactly*
the voltage your sparcbook transformer produces and at least the current output
(between 1X and 1.8X the current rating is OK). Both voltage and current should be
specified on the sparcbook's power supply.

I'm sorry that I don't have a product recommendation for you.

-Keith

nm wrote:

> "E. Keith Howick, Jr." wrote:
> >
> > I've used DC-to-AC converters in my car for years with laptops and radios. The
> > hum exists because the AC-sine wave is artificial, created by a simple series of
> > square waves. It will stress your power supply. I'd recommend looking for a
> > better brand of converter. Higher quality converters use more square wave
> > frequencies and better filtering to smooth the artificial sine wave, that'll get
> > rid of the hum and stop stressing your power supply.
> >
> > -Keith
>
> Shoot, thats what I was afraid of... Hmm... I assume that it would be a
> very bad idea to connect the sparc book directly to the output of the
> car's electrical system via a converter designed to run portable cd
> players?
> They are around $20 or so, and you can set them for a specific DC
> voltage
> from 1.5V to 6V.  Would this be a big no-no?
>
> Thanks
> Nick
>
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