5
DISCRIMINATION POINTS
By adjusting the TRASH REJECTION control you will be able to
reject (or “discriminate”) small pieces of metallic trash and
ground minerals while detecting valuable targets. The lowest
setting at which an object is rejected is referred to as the object’s
“discrimination point.” Discrimination points are determined by
such factors as size, shape, depth, type of metal and ground
mineralization.
Note:
the terms “discrimination” and “trash
rejection” are used interchangeably.
1.
Scatter some sample targets such as coins, pull
tabs and small pieces of foil on the ground 1 to 2
feet apart.
2.
Turn the TRASH REJECTION control to zero.
3.
Hold the search coil about 2 inches above and
parallel to the ground. Move it slowly over the
samples and note the sharp loud response as you
pass over each one. Keep in mind that the 1212-X
is a motion detector and responds only when the
search coil (or the target) is moving.
4.
Increase the TRASH REJECTION control to a setting
of 3 and again pass over the targets. Repeat this
process at settings 4, 5, 6 and so on to 10. You will
note that as you increase the level of trash
rejection, the 1212-X will reject some targets and
continue to respond to others. You have now
determined the discrimination points for the
rejected objects. For example, the small nail
discrimination point may be at 4 and the pull tab
discrimination at 6.
5.
The 1212-X will remain silent when some objects are
rejected, however, other objects may “snap,
crackle and pop” as they are rejected. This is a
perfectly normal response indicating that the
powerful discrimination circuitry is doing its job.
6.
Large pieces of trash such as beer cans or jar lids
may sound like a good target no matter what you
do. With a little practice, however, you will be able
to tell the difference between a large target and
a small coin-sized object.
