Basics Of Metal Detecting; Ground Minerals - Teknetics G2 Owner's Manual

ELECTRICAL INTERFERENCE (EMI)
You are likely to encounter electrical interference when using your G 2 metal detector. It
is important that you recognize electrical interference and take appropriate measures to
deal with it. This will prevent you from giving up on a worthwhile search site, or from
returning a properly functioning detector for repair.
Symptoms of electrical interference
Electrical interference can cause a metal detector to chatter spontaneously, to lose sensitivity
for no apparent reason, or to cause a periodic wobbly audio sound. What you hear will
depend on what operating mode you are using, the detector's settings, and the source of the
electrical interference. The most common manifestation is spontaneous chatter.
All metal detectors are susceptible to electrical interference, but they vary in what kinds
of electrical interference affect them. In a given environment some metal detectors may
be affected by electrical interference whereas others may not.
Common sources of electrical interference
Common sources of electrical interference include: overhead electric power lines,
underground power lines, other metal detectors, telephone lines carrying electronic
data, computer systems, electric fences, old CRT-based televisions, cell phones, CB
and emergency communication radios, thunderstorms, fluorescent lights, metal vapor
lamps, military aircraft with electronic warfare countermeasures turned on, electric
motors, VLF military communications systems and automobile ignition systems.
home, in a store, or in an urban environment, there may be several different sources of
electrical interference present simultaneously.
All metal detectors generate a certain amount of internal electronic noise. The G 2 is
specifically designed to enable you to work into the noise. Experienced users, striving
for maximum depth, often adjust the machine to search with a constant audible
background sound, and then listen through that noise for the sound of real targets.
Stricter regulations in recent years have cut down on interference from electric light
dimmers and auto ignition systems. However there has also been a proliferation of
VLF-UHF wireless communication systems (cell phones, Bluetooth, wi-fi, etc.), which
often affect metal detectors. Overall, the potential for electrical interference is greater
than it was just a few years ago.
Modern high-end metal detectors are a lot more sensitive than older units; this also
increases your detector's vulnerability to electrical interference beyond what you may
be accustomed to with an older detector. Metal detectors are by their nature designed
to detect magnetic fields, and electric current always produces magnetic fields.
Coping with electrical interference
The primary reason metal detectors provide a sensitivity (gain and/or threshold) control,
is so that users can reduce sensitivity in order to eliminate response to electrical
interference. Some users are reluctant to reduce sensitivity out of fear of losing depth.
At reduced sensitivity settings, you may lose some depth, but at least you can still
search. The Gain and Threshold knobs control the sensitivity and are your first
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THE BASICS OF METAL DETECTING
A hobby metal detector is intended for locating buried metal objects. When
searching for metals, underground or on the surface, you have the following
challenges and objectives:
1. Ignoring signals caused by ground minerals.
2. Ignoring signals caused by metal objects that you do not want to find,
like pull-tabs.
3. Identifying a buried metal object before you dig it up.
4. Estimating the size and depth of objects to facilitate digging them up.
5. Eliminating the effects of electromagnetic interference from other
electronic devices.
Your G 2 metal detector is designed with these things in mind.

1. Ground Minerals

All soils contain minerals. Signals from ground minerals can interfere with
the signals from metal objects you want to find. All soils differ, and can
differ greatly, in the type and amount of ground minerals present. You
therefore want to calibrate the detector to the specific ground conditions
At
where you are hunting. The detector incorporates both automated and
manual ground balancing features which will eliminate false signals from
most types of soils. To maximize the detector's target identification
accuracy and depth of detection, use the GROUND GRAB
to calibrate the detector to the ground where you are searching. See the
section on GROUND BALANCING for details.
® (GG) function
The Basics continued on next page
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