Thread: ringing bell in speaker
View Single Post
  #3  
Old 05-26-2008, 11:04 PM
wa2ise's Avatar
wa2ise wa2ise is offline
VideoKarma Member
  
Join Date: Dec 2002
Location: USA
Posts: 3,147
A microphonic tube can do that. A tube that has a loose control grid will modulate its electrons when a mechanical disturbance happens. Tapping the suspect tube sideways should make it go worse.
__________________
Reply With Quote