Tesoro Cibola Getting Started page 7

The SENSITIVITY knob is numbered from MIN to 10 and then has an orange area called the
Max Boost zone. For normal hunting, anywhere in the numbered zone will work very well.
However, the Max Boost will allow you to increase the power to the operational amplifiers to the
point of overload. This may cause your detector to become unstable and force you to turn the
SENSITIVITY knob to a lower setting. An overload situation will not hurt your detector, but it
will maximize the gain that is used by your detector. This can, in certain conditions such as low
mineralization in the soil, cause your detector to penetrate deeper into the ground and become
more sensitive to small targets.
Take some time to try waving targets in front of the coil with different sensitivity settings. Notice
that the higher the sensitivity setting, the farther away from the coil that a target can be and still
respond with an audio signal.
Perform Air Test in DISC Mode
As discussed before, the discriminate mode is used to filter unwanted targets from good targets.
The principle behind this is pretty simple. The detector sends out a signal and then receives it
back creating a small electronic field. As metal passes through the field that the detector
generates, it causes a change in the received signal. The amount of change that each type of
metal causes is fairly constant; therefore, we can tune our detectors to miss targets that we don't
want to find. The change is based on the type of conductivity that each target has. The general
list of conductive targets is as follows: iron, foil, nickels, gold jewelry, pulltabs, screw tabs,
pennies, and silver coins starting with dimes and working up to silver dollars. This list is only
meant to be a guide. There is a point that some pulltabs, nickels, and gold jewelry overlap. Also,
the depth of the target and its orientation in the ground can change the received signal. A coin
that is flat to the coil will produce a better signal than a coin that is on edge. Take some time to
try different combinations of depths and orientations of your targets and find out how your
detector responds.
We are now ready to discriminate targets from each other. We will start with the
DISCRIMINATE LEVEL at MIN. Please notice that the DISCRIMINATE LEVEL knob has
words that correspond to the items that are discriminated out.
All four targets (the iron, nickel, pulltabs, and quarter) will respond with a good audio signal at
the MIN setting. Next, we will turn the DISCRIMINATE LEVEL up to IRON. This should be