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line of defense against electrical interference. The Threshold control only applies to
the All Metal Mode.
Electrical interference is usually more controllable in the All Metal Mode than in the
Discrimination Mode.
On the G2, setting the discrimination level between 60 and 70 will usually reduce
electrical interference. In the Discrimination Mode, the detector may chatter if the
searchcoil is not in motion, but once you start sweeping it over the ground, the signal
from the ground will usually suppress the electrical interference chatter, except for an
occasional pop or click which will not sound like a real target.
If you are conducting an indoor demonstration, you may find that changing the
orientation of the searchcoil will reduce the pickup of electrical interference.
If you carry a cell phone or other high-tech electronic equipment while metal detecting
and you encounter electrical interference, try turning the device off and see if that solves
the problem. Turn such devices completely off, not just into standby mode.
When working near overhead power lines, you may get the best results right under the
power line and the worst results when standing at a 30° to 45° angle to the power line.
Many sources of electrical interference are intermittent. You may find that an area which
is difficult to search at one time of day may be easier after 5 PM, or on weekends.
Power lines are usually quietest late at night, and on weekend mornings.
Small searchcoils usually pick up less electrical interference than larger searchcoils. On
a site with severe electrical interference, a small searchcoil is often a better choice than
a large one.
Distinguishing electrical interference from other problems
Electrical interference will often vary as you walk around from place to place, and it will
also vary with changes in the orientation of the searchcoil. This is almost never the
case if there is a functional problem with the metal detector itself.
The most common cause of a noisy metal detector, where the problem is not electrical
interference, is a defective searchcoil. If striking the searchcoil with your hand causes
the noise to start or stop, the problem could be a defective searchcoil. Also, a defective
searchcoil often causes noise of a more intermittent nature than electrical interference.
The second most common cause is a loose searchcoil connector. The noise from a
loose connector will usually be very erratic or intermittent in nature. Try unplugging the
searchcoil and then reconnecting it to ensure the connector is firmly installed.
If you use a searchcoil cover, dirt or water can accumulate inside it, and movement of
those materials can cause false signals while sweeping the searchcoil. Searchcoil
covers must be periodically removed and cleaned.
ELECTRICAL INTERFERENCE (EMI)
X. Click the MODE knob to the right.
The detector is now in the ALL METAL Mode
a. Keep GAIN set at the 12:00 position
b. Rotate the THRESHOLD knob slowly from the far counterclockwise
position to the full clockwise position.
Notice these attributes of the THRESHOLD control, with no metal
over the searchcoil.
i. at low settings you will hear no sound
ii. at mid-scale, there will be a transition point from no sound to
a barely audible, choppy sound.
iii. at full scale you will hear a loud, constant tone. It may also have
an irregular or choppy sound, as a result of electromagnetic
interference emitted from other electrical devices.
Use with headphones (not included)
The G2is equipped with 1/4” headphone jack.Any headphones with a stereo plug
will work; headphones with a mono plug will not work. Using headphones extends
battery life, and also prevents the sounds from bothering bystanders. It also allows
you to hear subtle changes in the sound more clearly, particularly if searching in a
noisy location. Gold nuggets are often very small, so closely monitoring changes
in sound using headphones will improve your gold prospecting results. For safety
reasons, do not use headphones near traffic or where other dangers, like
rattlesnakes, are present. This device is to be used with interconnecting
cables/headphone cables shorter than three meters.
IX. Press-and-hold and hold the nickel over the searchcoil
a. Notice that motion is not required.
A motionless object induces a hum.
b. Notice the variable pitch & volume hum.
c. Move the nickel closer to and farther away from the searchcoil.
Notice the changing “depth” values.
QUICK-START DEMONSTRATION
