[PLUG] Darn RF!

[Keith Lofstrom]

On Mon, Mar 30, 2009 at 11:37:25AM -0700, John Jason Jordan wrote:
> Some time ago I bitched about feedback noise from the computer to my
> stereo. Think of a public address microphone where you get feedback
> weeooweeoowow because the microphone is positioned too close to the
> speakers.
...
> If anyone has any suggestions I'm all ears. Literally.

Feedback?  That is an open microphone somewhere, typically the one
on the laptop itself.  Can you disable it in the BIOS? 

Or perhaps it is the radio eavesdropping device implanted in your
house by FBI agents back during the J. Edgar Hoover era.  :-)

If your problem is actually bleedthrough from some other source, 
then sometimes cleaning the connectors so they make good contact
is helpful.  Sometimes Oregon dampness corrodes connectors, and
the corrosion acts like a diode, which rectifies radio signals,
which makes the diode and audio system behave like a crystal radio
receiver for AM signals.  

Or perhaps you need somebody to come take a look.  This kind of 
thing is difficult to diagnose remotely.

Keith

-- 
Keith Lofstrom          keithl at keithl.com         Voice (503)-520-1993
KLIC --- Keith Lofstrom Integrated Circuits --- "Your Ideas in Silicon"
Design Contracting in Bipolar and CMOS - Analog, Digital, and Scan ICs