Morton Jim@LLL-MFE.ARPA (10/25/85)
One possibility for Adam Epsteins howling is a microphonic active
component. One way to find these is to tap various components with
a non conducting whacker untill you either try all the parts or
find one that makes noise in the speaker when you tap the component.
Typically the noise in the speaker will be somewhat like the sound
of hitting the component.
73 Jim WA6FWW