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TEKNETICS
Comprehensive Operating Manual & Guide to Metal Detecting
TEKNETICS
Comprehensive Operating Manual & Guide to Metal Detecting
CAPABILITIES AND LIMITATIONS
DEPTH
The T
2
can detect U.S. coins to a depth of about 12-15 inches under good conditions. Large
objects (55 gallon drums, manhole covers, etc.) can be detected to a depth of several feet.
Electrical interference from power lines and from electrical appliances and electronic
equipment can reduce detection depth, or cause audible interference, making it necessary for
the user to reduce the sensitivity setting. Soils with large amounts of iron or salt minerals
may also reduce detection depth or necessitate a reduction in the sensitivity setting.
TARGET IDENTIFICATION
The T
2
identifies the probable type of metal object by measuring its effective electrical
conductivity, which is displayed as a number from 0 to 99 on the LCD screen. The effective
electrical conductivity of an object depends on its metallic composition, size, shape, and
orientation relative to the searchcoil. Since coins are minted to tightly controlled specifications,
they can be accurately identified. Identification of pull-tabs and foil is less consistent because
these kinds of targets come in wide variety. In general, smaller objects, and objects made
from lower conductivity alloys such as iron, bronze, brass, lead, pewter, and zinc will read
lower on the effective conductivity scale. Larger objects and objects made from higher
conductivity alloys such as silver, copper, and aluminum, will tend to read higher. The notable
exceptions are gold, which usually reads low because it is rarely found in large pieces, and
zinc pennies, which read moderately high because of their size and shape. Although nails and
other iron and steel objects will usually give low readings, ring-shaped pieces of iron (for
instance steel washers and harness rings) will usually produce medium to high readings. Flat
pieces of iron or steel, such as can lids, will occasionally do the same.
Most targets can be identified accurately in air to a distance of about 10 inches. The minerals
in many soils will cause identification to be less accurate. In most soils, effective target
identification can be had to a depth of at least 8 inches.
REQUIREMENT FOR MOTION; PINPOINT FEATURE
As with other modern metal detectors, the
T
2
’s searchcoil must be kept in motion in order to
both detect and identify targets. The All Metal mode is more forgiving of sweep speed
variation than is the Discrimination mode.
The trigger-activated PinPoint feature continues to detect metal if searchcoil motion stops over
the target. The PinPoint feature is used primarily to pinpoint the exact location of a target so
that it can be retrieved with a minimum of digging, and does not provide target identification.
ALL METAL MODE
The All Metal mode is more sensitive and offers better feel than the Discrimination mode, and
is used to find all metal objects present in the ground. The searchcoil must be in motion for
objects to be detected. This is a single filter search mode similar to the “fast autotune”,
“SAT”, or “P4” mode found in other detectors you might already be familiar with.
SENSITIVITY
This controls the electronic gain, and is adjustable from 1 to 99. In the
presence of electrical interference, high ground mineralization, or variable ground
mineralization, operation will usually be too noisy (wobbly and erratic sound from the speaker)
if the sensitivity is set too high. At settings above 90, the internal circuit noise of the machine
will probably be audible. The sensitivity level setting is largely a matter of personal
preference. However, if you cannot hear at least some noise, the smallest or deepest objects
will not be detected.
HUM LEVEL
This is the same thing that some manufacturers call audio threshold. It is
adjustable from -9 to +9. For maximum ability to hear the weakest signals, adjust this
background hum level high enough so that it is barely audible while the detector is in use in
the field. To eliminate the weakest signals, adjust the hum level into the negative region,
which will allow the machine to run silently if the Sensitivity is not set too high.
The hum level changes slightly with each detent step on the Settings knob. Each number on
the hum level numeric readout corresponds to five steps.
MANUAL GROUND CANCELLATION
Manual Ground Cancellation can only be performed while in the All Metal mode, but the
resultant setting will carry over if you change into Discrimination mode. See the previous
section on Ground Cancellation for instructions on how to use this feature.
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