[NJARC] tube shields and bucking

[sgt88 at atlanticbb.net]

Obviously, the metal tube shields protect the tube from stray EMF.

Has anyone done a 'before & after' - ie with & without shields to see what 
actually occurs?

Saw a note under the Philco 116 speaker drawing...'when replacing any part 
of the speaker, the hum bucking coil connections should be connected for 
minimum hummmmmmmm...

Hmmmmm...I see no part number for this "bucking coil"...nor ID on the 
drawing..."what's up?"