> I'd be surprised if this would turn out to be singing capacitor.
> Every switched-mode voltage regulator needs a an inductor, and
> these are much more likely to 'sing'. Probably you have a badly
> designed or specified regulator that fails when the load is
> below a minimum value (a classic problem with SM regulators).
> To test this, load the power supply e.g. via the USB connectors
> (a simple USB powered keyboard light could be enough).
> If you can locate the component, and it turns out to be an
> inductor, applying a bit of epoxy glue on the winding will
> probably silence it.
This is an EXCELLENT lead. Thanks Fons.
Can you give me a hint on how to identify an inductor? My notebook case
is open right now and the whine comes from a place out of or near the
CPU. Also, the whine comes when I start Jack at low latencies; I don't
quite understand what the purpose of loading the power supply would be;
I've hooked up my Palm Zire or a USB microphone (which sounded like
crap, but did load the power supply) and experienced no additional hum
whatsoever.
Carlo
Received on Thu Nov 16 08:15:03 2006
This archive was generated by hypermail 2.1.8 : Thu Nov 16 2006 - 08:15:03 EET