A device for locating an object behind a wall lining includes a housing having
a front portion fitting substantially in the palm of a user's hand. Operating switches
are located in juxtaposition to the grip portion so as to be operable by the user
without substantially altering grip on the housing. The device also includes a
sensor including a first capacitor plate and a pair of second capacitor plates.
The capacitor plates are arranged serially, and calibrated by a pulse width modulator
and integrator. Operating electronics are incorporated into an application specific
integrated circuit.
