>This is usually caused by the flyback transformer >windings or ferrite loosening up due to heat and >stress causing high frequency vibration or a >possible arcing. All the examples I have come across have a supersonic noise that drives me crazy, and it has always been because something electronic has died in the horizontal output stage and made the waveforms incorrect. The resulting incorrect waveform radiates sound from the mechanical vibration of the LOPT in an incorrect mode. I have yet to come across a unit where the problem has been a mechanically loose component. -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu