Quote Originally Posted by The Master View Post
Sorry, I'm not sure what you mean by "bobbin" (not in an electronics sense anyway).
What can I say now?
http://en.wikipedia.org/wiki/Bobbin

"in an electronics sense", the noise is generated at the ground of the circuit.
So, "in an electronics sense", a "bobbin" is used as the last component going to the ground of the power supply.
In other words, the "bobbin" is placed between the ground of the circuit and the ground of the power supply.

Usuallly, people make mistake by placing the "bobbin" to the positive supply and it makes no difference.

Quote Originally Posted by The Master View Post
Sorry, I'm not sure what you mean by "bobbin" (not in an electronics sense anyway).
Are you clear what I mean by "bobbin" now?