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TEKNETICS
Comprehensive Operating Manual & Guide to Metal Detecting
TEKNETICS
Comprehensive Operating Manual & Guide to Metal Detecting
CAPABILITIES AND LIMITATIONS (continued)
GROUND CANCELING
To achieve maximum depth in both the ALL METAL and DISCRIMINATION modes, as well as
when using the PinPoint feature, the T
2
offers the ability to cancel ground minerals either by
manual adjustment, or automatically using the FASTGRAB feature (see p.11).
If you do not perform the ground canceling operation, the Discrimination mode will usually still
work fairly well, but the ALL METAL mode will not. The Pinpoint feature can be used for
pinpointing objects at moderate depth in most soils without prior ground-canceling.
The internal computer will not automatically cancel salt water, so when detecting on wet ocean
beaches, ground cancellation must be done manually.
DISCRIMINATION
Discrimination refers to a metal detector’s ability to ignore metal objects in selected categories,
especially iron and aluminum. This makes searching much more pleasant in an area with a lot
of metal trash. The T
2
offers a wide variety of discrimination features which you can select
according to the search conditions and your personal preference.
DEPTH READING
The estimated Depth Reading displayed when engaging the PinPoint feature is based on the
strength of the signal. It is calibrated for typical coin-sized objects. Small objects will read
deeper than they actually are, and large objects will read shallower than they actually are.
AIR TESTING
There may be times when you want to test or demonstrate the metal detector without
sweeping it over the ground, for instance, if not fully assembled, or if you are indoors. To air
test, place the searchcoil in a spot where the detector is stable and more than two feet away
from any large masses of metal, including the reinforcing steel usually present in concrete. If
you are wearing a wristwatch or jewelry on your hand or arm, remove it. Then, test or
demonstrate by waving metal objects over the searchcoil; wave objects briskly, several inches
over the top of, and parallel to, the searchcoil.
Ground cancellation cannot be tested or demonstrated in air unless you happen to have
appropriate specimens of iron minerals available.
SWEEP SPEED
The T
2
is noted for its quick response. This gives it unsurpassed ability to locate and identify
good targets surrounded by trash. It also permits the user to sweep the searchcoil quickly in
order to cover more ground with very little risk of losing targets. In general, if you are
searching an area where the desirable targets are more than 8 to 10 inches deep, a faster
sweep speed will detect to a greater depth and yield more accurate target IDs.
CHECKING A TARGET
In order to most accurately verify a detected target with most other metal detectors, users will narrow
their sweep and loiter over the top of the target. The T
2
is different. The T
2
’s quick response and
advanced signal sampling system produces the most accurate target IDs with deliberate (shoulder
width) sweeps all the way across the target, even if there are other targets nearby. If you use a non-
standard sweep method or speed to check targets with the T
2
, the ID’s will bounce around more and
you run the risk of misidentifying the target.
GROUND CANCELLATION (continued)
MANUAL GROUND CANCELLATION (continued)
To perform the Manual Ground Cancellation operation, do the following:
1.
Select the MANUAL G.C. function
The legend G.C. PHASE appears.
The present ground cancellation setting is displayed (0-99).
The message PUMP COIL TO G.C. will appear.
2. Physically pump the searchcoil and detector up and down over the ground.
Lift it about 6 inches above the ground and lower it to within 1 inch of the ground,
about once or twice a second.
3. Turn the SETTINGS KNOB to adjust the level.
The goal is to eliminate the sound as the coil is being pumped over the ground. In
some soils, the sound is not completely eliminated; rather, the audio feedback is the
same both when lowering the searchcoil to the ground, and when lifting the
searchcoil off of the ground.
If the ground cancellation adjustment is incorrect, there will be a difference in the sound as the
searchcoil is either moving toward or away from the ground. It sounds like you are either
pulling the sound out of the ground, or pushing the sound into the ground.
• If the sound is louder as you raise the searchcoil, increase the ground cancellation setting.
• If the sound is louder as you lower the searchcoil, reduce the ground cancellation setting.
• NOTE: Experienced users often prefer to adjust the ground cancellation to get a weak but
audible response when lowering the searchcoil. This is called adjusting for positive response.
Positive and Negative Response
The purpose of ground cancellation is to adjust the metal detector to ignore ground minerals.
If the adjustment setting is off, ground minerals will give either a positive or negative response,
depending on which direction the adjustment is off.
POSITIVE RESPONSE
If the G.C. setting is too high a number, the response of minerals will be positive. This means that
when the searchcoil is lowered to the ground in PinPoint or All Metals mode, the sound will get
louder as the searchcoil approaches the ground. The sound will grow quieter as the searchcoil is
raised. What, if anything, you hear in discrimination mode depends on the discrimination setting.
When searching in All Metals mode, if ground cancellation is properly set to cancel the ground, and
you sweep over a positive hot rock, the rock will give a “zip” sound similar to that of a metal object.
NEGATIVE RESPONSE
If the G.C. setting is too low a number, the response of minerals will be negative. When the
searchcoil is lowered to the ground in PinPoint or in All Metals mode, the machine will be silent.
In All Metals mode, the machine will sound off as the searchcoil is lifted away from the ground.
What you hear, or do not hear, in Discrimination mode will depend on the discrimination setting.
When searching in All Metals mode, a negative hot rock will produce a “boing” sound after
passing over it, making it difficult to tell where it is located. It will not have the sound and “feel”
of a metal object.
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