🚀 go-pugleaf

In article <9012071856.AA07544@polar.bowdoin.edu> poulin@POLAR.BOWDOIN.EDU (Jeff Poulin) writes:
>"squeaks" (almost like bird chirps).  It sounds as if it's coming from the
>power supply, but at this point I'm too miffed and frustrated to draw any
>conclusions.  Any more help is greatly welcome.


I have "heard" switching power supplies under two circumstances.  One
is a sort of chirping effect when the power supply goes into it's
over-current shutdown mode, the other is simply changing high
frequency clicks as some program runs.  In both cases I believe the
source of the noise is the torridal core in the power supply itself.
Typically the windings work a little bit loose and then start to
vibrate under changing loads.  The chirping effect is usually
associated with a short on one of the supply voltages.  The high freq.
clicks are usually associated with some sort of cyclic high bandwith
activity, scrolling text, or zeroing ram, for example.  In fact the
workstation I'm using right now does it when I scroll one of my
X-windows.

								stank
US Mail: Stan Kalinowski, Tektronix, Inc., Network Displays Division
         PO Box 1000, MS 60-850, Wilsonville OR 97070   Phone:(503)-685-2458
e-mail:  {ucbvax,decvax,allegra,uw-beaver}!tektronix!orca!stank
    or   stank@orca.WV.TEK.COM