View Single Post
  #62  
Old 02-04-2011, 01:36 PM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
pretty sure it uses a switching power supply for the filament, that is what you are hearing, mine does it to, its pretty hi pitch, I would guess in the 10-12khz range.
Reply With Quote