Instruction Manual
Page 15
Discriminate / Pin Point Mode Switch
This switch selects either “Discriminate” or “Pin Point”
mode.
In “Discriminate” mode, the Discriminate (Disc) control
becomes active. This control can be used to ignore various
unwanted metal objects.
Metal objects fall into two broad categories: ferrous and
non-ferrous. A magnet can be used to determine if an object is a ferrous or
non-ferrous metal; ferrous metals will be attracted to the magnet while non-
ferrous metals will not. Generally while detecting, ferrous objects such as iron
and steel are not wanted, whereas the more valuable non-ferrous metals such as
gold, silver, and bronze are wanted.
In the “Discriminate” mode of operation and with the Disc control set to 1, the
Excalibur will ignore or “mask out” ferrous metal objects while still accepting
non-ferrous metal objects. In addition, target signals from non-ferrous objects
will vary depending upon their level of conductivity.
Effectively this allows you to identify the type of object detected before
recovering it from the ground. By way of example, a US quarter or Australian
$1 coin will produce a high pitch signal, whereas aluminum foil will produce a
low pitch signal. Pull-tabs, rings, and certain coins will produce an
intermediate pitch depending upon the object’s conductivity. The higher an
object’s conductivity, the higher the signal tone will be.
Additionally, in “Discriminate” mode, when the Excalibur detects a ferrous or
rejected non-ferrous object, the background threshold tone will momentarily
disappear and then return again at a pitch similar to the ignored signal. A
ferrous object will cause the returning threshold pitch to be much lower than
normal, while a pull-tab that is being ignored will cause the returning threshold
pitch to be higher than normal.
When in “Discriminate” mode, if the Excalibur produces a high-pitched rapidly
pulsing sound, the detector is being overloaded by a substantially large piece of
metal close to the coil. Raise the coil slightly above the ground and pass it over
the area again to check the target. By lifting the coil away from the ground, it
enables the Excalibur to analyze the object detected accurately.
