Graph Tech Ghost - Manual (Page 74)

74
Shielded cavity caveat
To improve noise immunity, the walls of the control cavity
are sometimes shielded, either with metal foil or conductive
paint (usually grey or black). This conductive shielding can
sometimes cause problems for the ghost® system. The ghost®
boards are not coated or insulated, so they must not touch the
cavity shielding. Mounting the boards on the shielding is okay,
as long as the foam tape on the back of the Acousti-phonic
board keeps the board separated from the shielding. If you
find it difficult to install the ghost® boards with space around
them to prevent touching the shielding, after you’ve plugged
in the pickups and all other connections, wrap the board(s) in
electrician’s tape to insulate the board from the cavity shielding.
In some instances, the cavity shielding can ironically cause
the ghost® system to pick up “buzz” or “hum” (sometimes
even radio stations)! Because it is a modular system, each
ghost® component comes with a ground wire. This abundance
of ground wires, combined with the pots and switches
being grounded through the shielding where they are
mounted, increases the likelihood of creating a ground loop.