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TEKNETICS

Comprehensive Operating Manual & Guide to Metal Detecting

TEKNETICS

Comprehensive Operating Manual & Guide to Metal Detecting

SEARCH TECHNIQUES (continued)

NUISANCE BURIED OBJECTS

In some areas there is a lot of metallic trash which produces weak signals. These could
include deeply buried objects, little bits and pieces of rusty iron and corroded foil. These items
can be detected, but are difficult to pinpoint due to their depth and small size.  When you dig
and find nothing, it may seem like the machine is beeping at nothing even though there is
actually something there.  The best solution is usually to reduce sensitivity.

If searching a very trashy area and unwanted signals are a problem, search with the
searchcoil 2 inches away from the ground.  Trash objects very close to the searchcoil will
sometimes not be completely eliminated, even when the discrimination setting should have
eliminated the target.

Metal detectors are designed to see one metal object at a time.  Where there are two iron
objects near each other, the detector can be fooled into thinking that the gap between them is
nonferrous metal.  This is a common condition where a wooden building has burned or been
torn down, and the site is littered with nails.  A signal from a nonferrous metal object such as a
coin will usually be repeatable, whereas a false positive signal resulting from multiple or oddly
shaped iron objects will seem to wander around and even to vanish.  Experienced detectorists
call these non-repeating signals and usually do not bother digging them since nonrepeating
signals are almost always trash.

GROUND MINERALS 

Conductive mineral salts usually produce broad signals which will not be mistaken for a
metallic object.  Common causes are concentrations of mineral fertilizer, spots where
evaporation has concentrated naturally occurring mineral salts, residue from de-icing salts,
and urine from livestock.  Unless dry, “cow pies” can sound off like they are metal.  Ocean
beaches have salt water—that subject is discussed elsewhere in the manual.

In spots where there has been intense fire, such as a campfire site or where a stump was
burned during land clearing, the soil minerals may be altered by oxidation so that their ground
cancellation setting is lower than that of the surrounding soil. In such cases, search slowly and
change the G.C. setting as frequently as necessary. 

In some areas, electrically conductive industrial minerals such as smelter coke, slag, and
charcoal have been dumped or used as landfill.  Individual lumps of these materials can
usually be quieted by reducing sensitivity and searching with a discrimination level of at least
50.  However, where the ground consists primarily of such materials, you may not be able to
search quietly.  In that case, do not dig unless a signal is crisp and repeatable.

Electrically conductive natural minerals such as graphite, graphitic slate, or sulfide ore
minerals are rarely encountered except when gold prospecting.  When gold prospecting, you
need to be able to hear everything, and you can expect to dig conductive minerals that turn
out not to be gold.  In a given locality you may learn to recognize what type of rocks these
minerals are found in, and to ignore them if people in the area say that gold is not found in
rocks of that type.

SPECIFICATIONS

Mechanical:  S-rod with electronics housing mounted on handgrip, 3-piece breakdown,
batteries under elbow, 2-way armrest adjustment — forward/backward & around forearm.

Searchcoil: 11” (28 cm) open-frame elliptical double-D, waterproof.

Batteries: 4 AA, alkaline or NiMH (not included).

Weight: 3.5 pounds (1.6 kg) with alkaline batteries installed.

Static Balance: force in vertical plane normal to elbow 0.47 pounds (0.22 kg).Varies with
adjustment and user’s stance and arm/hand physiology.

Dynamic Balance:  axial moment, 0.29 foot-pounds (0.39 newton-meters). Varies with
adjustment and user’s stance and arm/hand physiology.

Sweep Effort: lateral moment 5.2 foot-pounds (7.1 newton-meters).

Operating Principle: VLF induction balance

Operating Frequency: nominal 13 kHz, quartz crystal timing reference

Basic Sensitivity: 5 x 109 root Hertz (detectivity)

Lag Coefficient:  70 milliseconds

Reactive Overload: approximately 10,000 micro-cgs units (volume susceptibility)

Resitive Overload:  approximately 1,200 micro-cgs units (volume susceptibility)

Ground Cancellation Range:  From ferrite to salt, inclusive

Discrimination Ground Suppression: combination of second and third order methods

ID Ground Suppression: third order

Battery Life: typically 40 hours with good quality alkaline, somewhat less with NiMH rechargeable.

Operating Temp Range: -4 to +122 degrees F (-20 to +50 degrees C)

Operating Humidity Range: 0-90% non-condensing

TekneticsMANUAL.qx6  4/2/07  11:02 AM  Page 9

Summary of Contents for T2

Page 1: ...Professional Metal Detector Comprehensive Operating Manual and Guide to Metal Detecting ...

Page 2: ...ES Simple easy to use controls Large LCD screen with target identification and operating control displays Straightforward menu driven user interface Bar graph readout of ground mineral concentration Trigger actuated FASTGRAB ground canceling with manual override Waterproof 11 inch open frame BiAxial searchcoil Single Filter All Metal mode for maximum detection depth Double Filter Discrimination mo...

Page 3: ...1 Numeric Target Identification 19 Probable Target Identification 19 Target Depth 20 G C Phase 20 Settings 20 Messages 20 Bar Graph 21 Battery Indicator 21 Frequency Shifting 21 Capabilities Limitations 22 24 Tips Techniques Search Techniques How to sweep the searchcoil 25 Pinpointing targets 25 Estimating target size and depth 26 False signals and chatter 27 Adjusting Sensitivity 29 Tips on groun...

Page 4: ...l the detector should be silent 6 If you experience false signals from electrical interference from the soil itself or from lots of trash metal press the Menu button Sensitivity will be highlighted Rotate the Settings knob to the left counterclockwise Reduce the sensitivity setting until the false signals go away After 5 seconds the machine will exit the menu and return to normal operation 7 Toss ...

Page 5: ...round stem as follows Leave some slack in cable at base of lower stem Secure cable at base of stem with velcro strip Wrap cable loosely around entire stem up to bent part of s rod You will re wrap the cable later after sizing the rods to your height 7 Push cable into connector on back of housing Do not twist the cable or plug Turn knurled cap nut only 8 Tighten knurled cap nut by hand to secure ca...

Page 6: ...and outward To best stabilize the detector to your arm and body movement squeeze the sides of the arm rest around your forearm For a very secure fit some users prefer to bend the arm rest in tightly against the forearm such that you pry the sides loose each time you place your arm into the arm rest Firmly tighten bottom locking collar to secure lower stem 10 Attach cable to s rod with upper Velcro...

Page 7: ... securely As you swing the detector from side to side you want the bolts tight enough so that you do not feel any movement between the pole and arm rest mounting bracket If you notice unwanted movement while swinging detector check the tightness of the locking collars The locking collars must be rotated a full 270 to reach the locking position HEADPHONES not included The T2 is equipped with a stan...

Page 8: ...tion is adjustable to fit your arm The grip is durable high friction foam elastomer comfortable in any kind of weather The controls are conveniently located and easy to learn how to use Locking collars on the tubes eliminate rattling EASY TO USE INFORMATIVE INTERFACE The entire menu is always visible on the LCD display The LCD display indicates the electrical signature target I D of the detected m...

Page 9: ...ters Varies with adjustment and user s stance and arm hand physiology Sweep Effort lateral moment 5 2 foot pounds 7 1 newton meters Operating Principle VLF induction balance Operating Frequency nominal 13 kHz quartz crystal timing reference Basic Sensitivity 5 x 109 root Hertz detectivity Lag Coefficient 70 milliseconds Reactive Overload approximately 10 000 micro cgs units volume susceptibility R...

Page 10: ...ush of the menu button will recall that selection and display the stored value This recall function is useful for a value you want to adjust frequently such as the ground cancellation value SETTINGS Knob On the left of the front panel Rotate the SETTINGS knob to 1 Change the setting or value of the highlighted menu selection you have chosen 2 Select operating MODE when the top line of the menu is ...

Page 11: ... be displayed as a number To change a setting rotate the knob To increase a value rotate to the right clockwise To decrease a value rotate to the left counterclockwise If you select a function and do not make a change to that function after 5 seconds the detector will exit the menu system automatically and resume normal operation If you press the MENU button or rotate the SETTINGS knob while the m...

Page 12: ...detector is calibrated to the actual soil condition the result will be deeper target detection quieter operation and more accurate target identification This calibration or Ground Cancellation can be accomplished automatically with the detector s internal computer by pushing the Trigger Switch forward or manually in the All Metal menu The ground cancellation setting carries through into both All M...

Page 13: ...are a total of 500 different settings Under some ground conditions you may be able to hear the individual steps in the setting The Fe3O4 bar graph on the LCD display indicates the amount of magnetic mineralization The searchcoil must be in motion to measure Fe3O4 The most accurate measurement is obtained by pumping the searchcoil as in the Ground Cancellation procedure The two digit G C Phase numb...

Page 14: ...cellation 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 ...

Page 15: ...e 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 bar...

Page 16: ...s menu selection offers the user a choice among several different methods of audio discrimination to accommodate a variety of search conditions and personal preferences These methods differ in the way the signals are processed for analysis and in the number of audio tones used to identify different target types The detector has two ways of processing signals for analysis continuous and sampled Con...

Page 17: ... with a high concentration of steel bottle caps Also refer to p 23 for sweep techniques to aid in the identification of steel bottle caps 4 Four different audio tones This method is similar to 3 but with a fourth medium high tone for targets in the numeric range of 73 to 79 This four tone system is useful for searching in areas where there may be very old coins which register in this range dP Delt...

Page 18: ... the side of the target Then pull the trigger and raise the searchcoil about 2 inches Lifting the searchcoil away from the ground causes the ground signal to go negative the machine becomes silent Now move the searchcoil slowly across the target and the sound will communicate the target s location As you sweep from side to side and hear no sound at the ends of the sweep the target is located in th...

Page 19: ...me typically 83 U S quarter 25 coin clad typically 89 50 coin modern clad typically 92 old silver dollar coin typically 94 US silver Eagle 1 coin typically 95 PROBABLE TARGET I D The probable target ID zones at the top of the LCD display represent the signal ranges produced by various coins and types of metal objects When a metal target is detected the microcomputer analyzes the signal and categor...

Page 20: ...c soil is so close to the searchcoil that the signal is overloading the circuit the message OVERLOAD RAISE COIL will appear Such overloads will not harm the detector but the detector will not detect metals properly under these conditions Raise the coil until the message disappears the siren sound will also stop Resume normal detection The message RAISE COIL only appears when using the 3b or dP met...

Page 21: ...go dead the BATT legend will start flashing If using NiMH rechargeable batteries the display will remain stuck on the second or third bar for most of the battery life when it drops to the first bar the batteries will go dead within several minutes FREQUENCY SHIFTING One disadvantage of a highly sensitive metal detector is its susceptibility to electrical interference from other electronic devices ...

Page 22: ...ower 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...

Page 23: ...etector 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...

Page 24: ...istently It also produces more audio clues to the character of the target 3 Lift the searchcoil or sweep at an angle Within 2 inches of a Bi Axial searchcoil the crossed magnetic fields of the Double D construction can produce anomalous responses If the object feels shallow strong signal narrow response or multiple responses in a single sweep and is giving consistent high readings like a coin rais...

Page 25: ...ge Targets If an overload warning is not confined to a small spot you are probably overloading on a large object for example a large iron pipe reinforcing steel in concrete or buried sheet metal It is usually not possible to locate objects such as coins in close proximity to large masses of metal Pinpointing With the Trigger Switch When you turn the T2 on the ground cancellation setting is preset ...

Page 26: ... a broad response the target is probably an aluminum can Practice this by laying a coin and a flattened aluminum can on the ground you will quickly understand how to differentiate the two and will probably never have to dig another aluminum can again And you will know whether it was deep or shallow This technique works well in the All Metal mode and to a lesser extent in Discrimination mode Object...

Page 27: ...d be obtained in an air test This tendency is connected with the T2 s enhanced see through ability that is the ability to find valuable targets in an area where there is a lot of iron trash False Signals and Chatter At times the detector may beep when there is nothing there or it may seem like there is nothing there There are five major causes for this electrical interference nuisance buried objec...

Page 28: ...ve mineral salts usually produce broad signals which will not be mistaken for a metallic object Common causes are concentrations of mineral fertilizer spots where evaporation has concentrated naturally occurring mineral salts residue from de icing salts and urine from livestock Unless dry cow pies can sound off like they are metal Ocean beaches have salt water that subject is discussed elsewhere i...

Page 29: ...and are common in many gold prospecting areas They are usually but not always drawn to a magnet They are most often reddish in color but are often black brown or yellow On relic hunting sites red clay bricks and rocks which have lined a fireplace or a campfire will often be hot rocks The discriminator will usually eliminate them without difficulty if widely scattered but if there is a large concen...

Page 30: ...ce preset will be restored and then use the machine without ground canceling In most areas once you have ground cancelled the ground cancellation setting will remain satisfactory for a long time However if the soil has been disturbed by digging or the addition of fill dirt or if you are in a geologically complex setting such as is commonly encountered in gold prospecting areas you may have to freq...

Page 31: ...ot like even if there is no ordinance against it If there is a metal detecting club in your area someone will usually know what areas can and cannot be searched Be prepared to always put your best foot forward when using a metal detector in a public place Pick up any trash you recover put it in a pouch or pocketed apron This way you can explain that you are performing a public service by helping k...

Page 32: ...tion and within that collection document the circumstances surrounding each button found If your finds are mixed together without categorization or documentation their context will be lost The ground cancellation and Fe3O4 bar graph features of the T2 can be used to map the soils of a site In this way you might determine which areas have been dug backfilled or subjected to fire This information in...

Page 33: ...n the language of the sounds you hear Headphones are recommended unless consideration for safety for instance rattlesnakes rules them out Move the searchcoil slowly and deliberately carefully controlling its height above the ground to minimize noise from iron minerals in the soil If you hear ground noise your Ground Phase setting could be a bit off so perform the ground cancellation procedure agai...

Page 34: ...e and deep Searching in All Metal mode is recommended However for a really deep cache it may be advantageous to search in Pinpoint frequently releasing the trigger momentarily to maximize sensitivity Shallow Water Hunting All First Texas Products searchcoils are waterproof allowing you to search in shallow water about two feet deep If searching around water be careful not to get the electronics ho...

Page 35: ...o distinguish between ferrous and nonferrous metals The other coil is a receiving antenna which detects changes in the magnetic field caused by the presence of metal Electronic circuits amplify this weak signal analyze it to determine the changes which occur as the searchcoil sweeps over the target and then convey the information to the user in the form of a visual display or audio tones Most mode...

Page 36: ...lity under this Warranty is limited to replacing or repairing at our option the metal detector returned shipping cost pre paid to First Texas Products Shipping cost to First Texas Products is the responsibility of the consumer To return your detector for service please first contact First Texas for a Return Authorization RA Number Reference the RA number on your package and return the detector wit...

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