GARRETT AT Pro™ International, Owner's Manual

TM

The powerful, all-terrain solution for locating deeply buried European coins and artefacts!

1881 W. State Street

Garland, Texas 75042

Tel: 1.972.494.6151

Email: [email protected]

Fax: 1.972.494.1881

© 2012 Garrett Electronics, Inc. PN 1533300.C.1012

Owner’s Manual

THANK YOU FOR CHOOSING

GARRETT METAL DETECTORS!

Congratulations on the purchase of your new Garrett AT

Pro™ metal detector. This enhanced metal detector has been specifically designed for use in Europe's challenging environments.

AT Pro includes Garrett's exclusive Target ID technology and patented discrimination features. Two indicator scales allow you to see the detector’s discrimination setting (Lower

Scale) as well as the analysis of each target (Upper Scale).

In addition, a Digital Target ID scale provides a more specific target value. The AT Pro also features High Resolution

Iron Discrimination (40 points) for separating desirable targets from iron junk in cluttered areas, several advanced audio features and a standard 28x22cm elliptical Double-D searchcoil engineered for optimum performance in Europe's more challenging mineralised soils. In addition, the AT Pro can be operated in a very user-friendly Standard (STD) Mode or in a more advanced PRO Mode for experienced hunters.

Backed by more than 45 years of extensive research and development, your Garrett AT Pro metal detector is the most advanced of its kind in the industry. Whether you are experienced or a beginner, this machine is well suited for a wide variety of detecting environments. The AT Pro's advanced features are designed for the expert treasure hunter but its Standard Mode can be easily operated by the beginner.

In order to take full advantage of the special features and functions of the AT Pro, you are urged to carefully read this instruction manual in its entirety.

AT Pro International™ 1

2 Garrett Metal Detectors

TABLE OF CONTENTS

AT PRO CONTROL PANEL ................................................................... 4

QUICK START GUIDE ........................................................................... 5

AT PRO COMPONENTS ....................................................................... 6

LIST OF PARTS .................................................................................... 7

ASSEMBLY .......................................................................................... 8

POWERING ON .................................................................................. 11

SEARCH MODES ...............................................................................12

Overview of STD Mode vs PRO Mode ........................................12

Standard (STD) Detection Modes .............................................. 13

PRO Detection Modes ................................................................ 15

Proportional Audio (PRO Mode) ................................................. 15

Tone Roll Audio (PRO Mode) ...................................................... 18

TARGET ID INFORMATION ................................................................ 19

DIGITAL TARGET ID ...........................................................................20

TONE ID ............................................................................................. 21

DISCRIMINATION ..............................................................................22

Notch Discrimination..................................................................22

Iron Discrimination ..................................................................... 24

IRON AUDIO ...................................................................................... 27

SENSITIVITY ......................................................................................30

GROUND BALANCE ........................................................................... 31

Automatic Ground Balance ........................................................ 31

Manual Ground Balance ............................................................32

FREQUENCY ADJUSTMENT ..............................................................33

PINPOINTING ....................................................................................34

Narrowing the Detection Area ...................................................36

Coin Depth Indicator ..................................................................36

Alternative Pinpointing Methods ............................................... 37

HUNTING TIPS ..................................................................................39

BENCH TESTS ...................................................................................44

UNDERWATER OPERATION .............................................................. 47

CARE AND MAINTENANCE ...............................................................48

Battery Replacement .................................................................48

TROUBLESHOOTING GUIDE .............................................................50

METAL DETECTING CODE OF ETHICS ............................................. 51

CAUTIONS .........................................................................................52

WARRANTY / SERVICE .....................................................................53

ACCESSORIES ...................................................................................54

SUGGESTED READING .....................................................................56


AT Pro CONTROL PANEL

Target ID

Legend indicates metal types.

High Resolution

Iron Discrimination indicates level of iron discrimination selected.

Digital

Target ID

(also shows ground balance settings while in

GND-BAL mode.)

Target ID

Cursor indicates probable target identity.

Mode

Indicator

Sensitivity

Setting

Lower Scale indicates notch discrimination pattern.

Coin Depth

Indicator indicates depth of coin-sized target.

Iron Disc

Pushbutton

Use (+) or (-) to change iron discrimination level.

Iron Audio

Use to hear discriminated iron.

ON / OFF Power: hold 1 second to turn power on/off.

MODE: push quickly to toggle between detection modes.

RESET: hold 5 seconds to restore factory settings.

PINPOINT /

Frequency

Adjust

Pushbutton

Press and hold to pinpoint or use with

SENSITIVITY (+) or (-) to change frequency.

SENSITIVITY

Pushbutton increases or decreases sensitivity.

Battery Level

Indicator

GROUND BALANCE

Pushbutton

Press and hold for fast auto ground balance or use with

NOTCH DISC (+) or (-) for manual ground balance.

ELIM and NOTCH DISC

Pushbuttons

Use NOTCH DISC (+) or (-) to select a cursor. Then use ELIM button to set its discrimination on or off.


QUICK START GUIDE

1. Install batteries.

The

already installed by Garrett.

2. Power ON.

Press and release the ON / OFF Power button. The AT Pro

powers on in the last mode used and is ready to search.

(Factory default mode is Coins.)

3. Select Mode.

Use the Mode Pushbutton to select a different detection

mode, when desired.

4. Adjust settings.

Adjust Sensitivity or Discrimination settings, if desired.

5. Begin scanning.

Lower the searchcoil to 2 to 3 cm above the ground and

scan the coil left and right at approximately 1m/second.


AT Pro COMPONENTS

Search coil

Lower

Stem Upper

Stem

Control

Housing

Camlocks

S-shaped

Stem

LCD

Screen

Pushbutton

Controls

Arm strap

Handle

Grip

Detector

Stand Padded

Arm Cuff

LIST OF PARTS

No tools are required to assemble the AT Pro. Four (4) AA batteries are included with the detector. The box for your detector contains the following parts:

 One (1) control housing with

S-shaped stem

 One (1) upper stem and one

(1) lower stem connected,

with camlock fasteners

 One (1) wing nut, two (2)

mounting washers and

one (1) threaded bolt

 One (1) 28x22 cm DD

searchcoil

 Owner's manual

 Warranty Card

 Headphones

If any part is missing, please contact your local dealer.















6 Garrett Metal Detectors AT Pro International™ 7

ASSEMBLY

1. Holding the upper and lower stem assembly in front of you (as shown below), twist camlock to the right (clockwise) to loosen.

2. Slide lower stem out to engage spring clips in upper stem holes.

3. Align the holes in the mounting washers with the small posts on the lower stem and press firmly into place.

1. 2. 3.

7. Depress the spring clip in the S-stem (containing control housing)

and insert S-stem through the upper camlock collar into the upper stem.

8. The spring clip must be engaged in the FIRST stem opening in

order to maintain battery compartment access. Hand-tighten the camlock collar. Do not overtighten!

7. 8.

1st pin position

4. Slide the searchcoil onto the stem.

5. Insert the threaded bolt through the holes of the lower stem and searchcoil. Hand-tighten searchcoil assembly with the wing nut.

6. Holding assembly as shown, loosen camlock at the end of the upper shaft by turning counter-clockwise.

Note: If the camlock collar slides off during loosening, simply slide it back on and tighten slightly.

4. 5. 6.

9. Depress the spring clip in the lower stem and adjust to the most

comfortable operating length. Hand-tighten the lower stem camlock collar. Do not overtighten!

10. Wrap the cable snugly about the stem with the first turn of the cable over the stem.

9. 10.


11. Insert the coil connector into the 4-pin connector of the control

housing and hand-tighten. After lining up the connector pins, press the connector in firmly, yet carefully, until the O-ring is felt to be fully inserted.

11.

Note: If the O-ring is properly seated, the connector's collar can be easily tightened; if the collar is difficult to turn, the

O-ring may not be seated

properly.


12. If needed, adjust the arm cuff by removing the screw on the

bottom. Move the two-piece cuff to the other hole, reinsert the

screw through the headphone cable clip, and tighten.

12. 13.

13. If desired, attach headphones to the 2-pin connector of the

Control Housing. After lining up the connector pins, press the

connector in firmly, yet carefully, until the O-ring is felt to be

fully inserted.

14. Secure the headphone cable under the detector's arm cuff by

pressing the cable into the headphone cable clip.

Note: Headphones are not required but are desired by many

hunters to hear faint targets. Connecting the headphones will

silence the detector's speaker.

Note: The provided headphones are for dry use only; see page

54 for optional waterproof headphones.

14.


POWERING ON

ON/OFF Power and MODE

Pushbutton

Switch the detector on with the power button.

Press and release to switch the unit ON and resume hunting with the same settings used prior to switching the unit OFF.

To turn off the detector, press and hold this pushbutton for one (1) second (until the detector produces a second beep).

To restore the factory settings, press and hold the power button for 5 to 10 seconds (until the detector produces a fast double beep).


SEARCH MODES

(STD) Modes and three Professional (PRO) Modes. It is recommended to begin searching with one of the Standard

Modes to become familiar with the AT Pro before switching to the more advanced audio features provided by the Pro

Modes.

Tap the Mode button to scroll through the six modes: the modes are Custom, Coins or Zero in the STD Mode and

Custom, Coins or Zero in the PRO Mode.

• Overview of STD Mode vs PRO Mode

In its Standard (STD) Mode, the AT Pro provides a fullstrength audio response regardless of a target’s amplitude.

Many detectorists prefer this consistent, unambiguous, binary

(either on or off) target response. The AT Pro's Standard Mode operates in this clean, binary response format in which the target's dominant conductivity is reported by a single tone.

This mode offers "quieter" or more stable operation and is preferred by many beginners.

For those who want to hear more target information,

Garrett offers a Pro Mode. The benefits of operating in Pro

Mode include the ability to hear a target's size and depth via the Proportional Audio and conductivity changes via Tone

Roll Audio. Pro Mode also offers faster recovery speed for separating adjacent targets. The advanced audio features of

Pro Mode are intended for more skilled users who wish to hear the true signature of targets versus the simpler target response provided in STD Mode.


STANDARD (STD) DETECTION MODES

In the STD modes, the AT Pro produces a full-strength binary audio beep to indicate a detected target. Standard detection mode operation is ideal for learning the AT Pro because of its consistent audio signals. Detected targets are heard at the same full-strength beep regardless of their size or depth.

Three discrimination patterns are available in the

Standard Mode: Zero, Coins or Custom.

Note: These three discrimination patterns are the same in either Standard or Pro modes.

• ZERO Mode

Designed to detect every type of metal; use

ZERO mode to find all metal items or when the material of the desired object is unknown. All 12 discrimination pixels are switched on and High-Res

Iron Discrimination is set to 0 (zero)—indicating that no metal targets have been eliminated.

Switch to the ZERO Mode to aid in locating a target when its signal is inconsistent. Such signals could mean the target is made of iron or a trash target is close to a good target.


• COINS Mode

Designed to find most types of coins, jewelry, etc., while eliminating trash items such as iron and foil.

High-Res Iron Discrimination level has been preset to 35 to exclude most iron targets. In addition, one pixel of foil has been excluded. Be aware that most pulltabs and pieces of tabs have not been eliminated from detection as these trash items have conductivities similar to small coins and jewelry.

• CUSTOM Mode

This mode can be customized by the operator and the AT Pro will retain the changes when the detector is switched off. The factory preset for the CUSTOM

Mode is the same as the ZERO Mode (see previous page). Begin with this discrimination pattern and then use IRON DISC and NOTCH DISC pushbuttons to customize the discrimination settings.

Note: Changes made to the ZERO or COINS modes will not be retained after the detector is switched off. (For information on the use of IRON DISC and NOTCH

DISC, see pages 22–26.)


PRO DETECTION MODES

Zero, Coins or Custom have the same discrimination patterns as in STD Mode. In PRO Mode, however, the AT Pro utilizes its Pro Audio functions—including Proportional Audio and Tone Roll Audio—to offer more target information.

The Pro Mode audio provides more target information and faster recovery speed for separating adjacent targets. This is especially important in areas where good targets may be scattered amongst iron trash.

Pro Mode audio by its nature creates more audible chatter than Standard Mode. This is normal because of the additional sensitivity of Pro Mode. The audio depth can exceed Target ID depth in Pro Mode so it is possible to hear deep targets that do not register a Target ID.

Proportional Audio (Pro Mode)

Proportional audio response means that the loudness of the target's response is proportional to a target's signal strength. This allows the user to hear subtle changes in a target’s response. Proportional audio response also allows the user to better judge a target’s size, shape and depth and has the additional benefit of faster recovery time for separating adjacent targets.


Audio Target Response Comparison: Standard vs Pro Mode Adjacent Targets Comparison: Standard vs Pro Mode

Shallow coin

Deep coin

Notice the differences in Standard binary audio versus PRO audio in the two target scenarios above. The binary audio gives a solid, consistent beep for both the shallow and the deep coin. In contrast, PRO Mode's proportional audio provides a stronger signal for the shallow coin and a softer signal for the deeper coin. The actual profile, or signature, of the target’s response is heard, thereby providing more information.

Adjacent targets

These two adjacent coins would produce one strong signal while in STD Mode.

In PRO Mode, the proportional audio provides two peaks of audio response to allow the user to identify multiple targets.


Tone Roll Audio (Pro Mode)

This feature of Pro Mode provides the user with more audible target information to help identify targets, particularly flat iron objects, such as bottle caps and washers. Standard

Mode audio produces a single tone based upon the target’s strongest signal. For flat iron objects, this single tone is often the same as a good target. Tone Roll Audio, however, provides a variance of target tones as the searchcoil approaches and passes over the target. These varying tones of audio provide better overall target information and identification.

Tone ID Comparison: Standard vs Pro Mode

Bottle cap Coin

While in STD Mode, bottle caps, steel washers and other flat iron objects often sound like good targets, producing a high tone response. This is because the bottle cap’s shape and flat surface resembles a coin which can trick the detector. In PRO Mode, however, the bottle cap will produce a very distinctive response with multiple tones. As shown, the bottle cap will produce a distinctive response of Low-High-Low as compared to the coin’s response of only High tone.


TARGET ID INFORMATION

Target ID Legend Target ID Cursor

(Upper Scale)

Discrimination

Pattern (Lower Scale)

Target ID Legend —Works in conjunction with the Target ID

Cursor to indicate a target's probable identity. Ferrous (iron) targets will indicate on the left half, non-ferrous targets that are thin or have low conductivity will indicate in the middle, and thick or high conductivity targets (e.g. thick silver) will indicate at the right.

Target ID Cursor (Upper Scale) —The Target ID cursor, in conjunction with the Target ID Legend, indicates the probable identity of a detected target. The upper scale consists of twenty (20) graphic segments for Target ID.

Lower Scale —The lower scale, or Notch Discrimination

Scale, continually indicates the discrimination pattern. The AT

Pro will produce an audible target response for the pixels that are switched on, and no audible response for those that have been switched off. The Target ID Cursor will always indicate all targets.

The discrimination pattern can be adjusted (as described

in the "Discrimination" section).


DIGITAL TARGET ID

Digital

Target

ID

Target ID

Cursor

The AT Pro’s Digital Target ID system provides a specific target value to help identify targets more precisely. Targets are identified on the LCD by number, with items near 1 being the most ferrous. The most conductive targets (such as thick silver) register closer to to 99.

The Digital Target ID is a more precise version of the

Target ID Cursor shown in the Upper Scale. Each Target ID

Cursor has a width of 5 digital points. For example, a Digital

Target ID of 73 will light the cursor from 70 to 75.

This system, when used in conjunction with the audio target signals, provides you with more information. The sample chart on the following page provides Digital Target ID ranges of some commonly found items.

It is important to note that while operating in the PRO

Mode, the Pro Audio depth can exceed Target ID depth (i.e. faint targets at depth can be heard without providing any

Target ID).


Note: Target values can vary based on the orientation of the target in the ground, amount of ground mineralization, etc. It is important to practice in the field to learn how these factors can affect Target ID.

TONE ID

The Tone ID feature produces three distinct audible tones based on a target’s metal type and conductivity:

Low-Tone: Ferrous targets such as nails, iron,

Medium-Tone: Small, thin targets that are non-ferrous, such as small jewelry, foil, and some very thin, hammered coins.

High/Bell Tone: Non-ferrous targets with medium to high conductivity, including most coins and tone; STD Mode produces a bell tone.


DISCRIMINATION

Notch Discrimination —The AT Pro's NOTCH DISC pushbuttons are used in conjunction with the ELIM pushbutton to eliminate trash objects from detection such as foil or pulltabs.

Example: Manual Modification of Notch Discrimination Pattern

Use the NOTCH DISC buttons to position the Target ID Cursor above the pixel you wish to eliminate (see above illustration). Use the ELIM pushbutton to delete this pixel from the Lower Scale (see below). This item is now rejected.

NOTCH DISC

Pushbutton

ELIM

Pushbutton

AT Pro has 12 pixels or "notches" of discrimination (in addition to the 40 points of High-Res Iron Discrimination).

Any combination of these pixels can be switched on or off based upon your preference. There are two primary methods for modifying the Notch Discrimination Pattern to reject a specific type of trash or unwanted item.

The first method uses the NOTCH DISC and ELIM pushbuttons (seen above) to manually modify the Lower

Scale's Notch Discrimination pattern.

Use the (+) or (-) NOTCH DISC pushbuttons to move the

Target ID cursor to the left or right. Next, press the ELIM pushbutton to eliminate or activate the pixel located on the Lower Scale, directly below the Target ID cursor. (See illustrations on next page.)


The second method of modifying the Notch Discrimination pattern involves the use of only the ELIM pushbutton. When an unwanted target is audibly detected while hunting, simply push the ELIM button to create a notch at that Target ID

Cursor. The next time the AT Pro encounters the same trash item, it will not produce an audible signal.

AT Pro's ELIM pushbutton can also be used to find

specific metal items. For example, if an earring has been lost, scan the matching earring with the AT Pro while in the

ZERO mode. Note where the Target ID cursor appears when the earring is scanned. Next, use the NOTCH DISC and ELIM pushbuttons to switch off all the pixels except the one for the earring.

Note: Depending upon how the lost earring is laying in the ground, its Target ID may shift a little; therefore, your ability to find it will be enhanced by turning on an additional pixel


on either side. The AT Pro is now programmed to find the missing earring based on the conductivity of its matching pair.

Note: The notch discrimination function can be used to modify each Mode’s discrimination pattern. Notch

Discrimination modifications made while in CUSTOM (either in Standard or Pro mode) will be retained when the detector is switched OFF. However, all changes made to the Notch

Discrimination pattern while in ZERO or COINS modes will return to the factory settings when the detector is switched

OFF and back ON again.

Iron Discrimination —The AT Pro features a high-resolution iron discrimination adjustment. This additional resolution allows more precise control of how much iron discrimination can be applied. The level can be adjusted from 0 (no iron discrimination) to 40 (maximum iron discrimination).

High-Resolution Iron

Discrimination Setting

IRON DISC Pushbutton

Use the (+) or (-) IRON DISC pushbuttons to adjust the Iron

Discrimination up or down.

The small two-digit number above the words "IRON DISC" on the LCD indicates the iron discrimination setting.


The examples shown below illustrate how an iron object can often "mask" out the signal of an adjacent good target when too much iron discrimination has been applied.

Using the AT Pro's High-Res Iron Discrimination, apply just enough iron discrimination to reject the undesired iron nail shown in this example. By using only a minimal amount of iron discrimination, the detector will detect the combined conductivity of the coin and nail together thus overcoming the potential "masking" problem.

Illustration 1 Illustration 2

Iron targets, such as the nail shown in Illustration 1, can sometimes mask a good target's signal. If too much iron discrimination is applied, the good target (seen in Illustration 2) can be missed.

Read page 26 to learn how to apply the proper amount of iron discrimination to eliminate the nail shown in Illustration 1 and still detect the good target shown in Illustration 2.


Example: Detecting Targets in Trash with High-Res Iron Discrimination

IRON AUDIO

In the illustration above, the AT Pro is operating with an IRON DISC setting of

20. The nail seen in Illustration 1 (on page 25) registers from 10 to 25 on the

Digital Target ID scale. To eliminate the nail from detection, increase the iron discrimination level to 25 using the IRON DISC (+) pushbutton.

In Illustration 2, the same iron nail is laying above a good coin target. Since the Iron discrimination level is set to 25, the nail by itself would not be detected; however, the two objects have a combined conductivity of more than 25.

Therefore, the good target is detected due to the combined conductivity being higher than that of the discriminated target (nail) alone.


Iron Audio

ON

IRON

AUDIO

Pushbutton

Press and release the IRON AUDIO pushbutton to switch the

Iron Audio feature ON/OFF. When this feature is on the words

"IRON AUDIO" appear on the LCD (as shown in the illustration

above). The Iron Audio feature can be used in any of the AT

Pro's six modes.

Scattered iron objects in the ground can mask good targets and even create “ghost signals” that appear to be a good target. Garrett’s selectable Iron Audio feature allows the user to hear discriminated iron (normally silenced) in order to know the whole picture and avoid being tricked into digging an undesired target.

Iron Audio also allows adjustment of the mid-tone’s range to include all targets above the iron discrimination setting.

The user is adjusting the cut-off between low-tone iron targets and mid-tone targets to better distinguish good targets.


Refer to the illustrations below regarding the use of the Iron

Audio feature:

IRON AUDIO OFF: Normal division of low, mid and high tones.

IRON AUDIO OFF: With the Iron Discrimination set to 20, all targets below

20 are silent.

iron object like a bottle cap or steel washer will produce a very distinctive Low-High-Low response.

Tip for using Iron Audio: In areas with high concentrations of iron, it is recommended to switch off Iron Audio. Otherwise, it may produce far too many signals. Then, if a target is detected that has a questionable or inconsistent response, switch on Iron Audio to check if it is iron.

To fully appreciate the additional information offered by the Iron Audio feature, conduct the following experiment.

Start with the AT Pro in Standard (STD) Zero Mode and pass the searchcoil over a bottle cap which is lying flat on the ground. Note that the target response is consistent with the audio of a good target.

Then, switch the detector into PRO Zero Mode and pass the searchcoil over the bottle cap again. Note the subtle low tones at the beginning and end of the target response, indicating a questionable target that might be made of iron. Finally, set IRON DISC to 35, switch on Iron Audio and pass the coil completely over this target again. The distinctive Low-High-Low response now indicates a target that is unmistakably iron.

IRON AUDIO ON: Targets below 20 are now heard as a low tone and targets above 20 will produce a mid or high tone.

When Iron Audio is on in the PRO Mode, iron targets will not only be heard, but they will produce an even more distinctive response with multiple tones. For example, a nail will produce several fast low tones as the searchcoil passes over. A flat


SENSITIVITY

SENSITIVITY

Pushbutton

Sensitivity

Indicator

AT Pro has eight (8) settings for sensitivity. Use the (+) or (-) SENSITIVITY buttons to step through the eight levels, which are continuously shown on the LCD.

Use higher sensitivity levels when searching for very small or very deep targets. Use lower sensitivity levels in locations where the detector is behaving erratically due to excessive metallic trash, highly mineralized soils, saltwater beaches, electrical interference or the presence of other metal detectors.


GROUND BALANCE

GND BAL

Indicator

(only displays on

LCD when in use)

GND BAL Setting

(only displays while in Ground

Balance mode)

NOTCH DISC

Pushbutton

(use with GND BAL)

GND BAL

Pushbutton

GND BAL Pushbutton—Hold for Automatic Ground Balance or use in conjunction with the NOTCH DISC pushbuttons for

Manual Ground Balance.

Detector performance can be negatively affected by ground mineralization. The AT Pro can be ground balanced either automatically or manually to cancel unwanted ground signals and obtain maximum stability and target detection.

Automatic Ground Balance: Press and hold the GND BAL pushbutton while continually "bouncing" or "pumping" the searchcoil from 2 to 20 centimeters above the ground. When there is a minimal audio response from the ground, release the pushbutton and begin hunting. The ground balance value will have been indicated in the center of the LCD. Low ground


balance values indicate conductive soil; high ground balance values indicate ferrous soil.

Manual Ground Balance: You may want to use the Manual

Ground Balance function to ground balance slightly positive to enhance detection of small targets or balance slightly negative to reduce detection of "hot rocks," terra cotta and saltwater.

Press and release the GND BAL pushbutton and continually bounce (pump) the searchcoil from 2 to 20 cm above the ground. If low tones are produced, increase the Ground

Balance setting using the (+) NOTCH DISC pushbutton. If high tones are produced, decrease the setting using the (-) NOTCH

DISC pushbutton. Press and release the (+) or (-) NOTCH DISC pushbuttons to make single-step adjustments, or press and hold to make large adjustments.

Continue bouncing the coil and making adjustments until a minimum audio response is obtained, indicating the detector is ground balanced. The Ground Balance setting will be indicated on the LCD.

Press and release the GND BAL pushbutton again to exit

Manual Ground Balance mode. The Ground Balance setting will be retained when the detector is switched OFF.

Typical Ground Balance Ranges:

80–99: Highly ferrous (magnetite, ferrous oxide minerals, black sands, hot rocks, terra cotta)

60–80: Moderately mineralized soils (red clay, brown clay, iron-bearing clay minerals, etc.)

20–60: Likely an iron object

0–20: Highly conductive, non-ferrous minerals such as saltwater


FREQUENCY ADJUSTMENT

SENSITIVITY

Pushbutton

PINPOIINT/

Freq Adjust

Pushbutton

Use the PINPOINT/Freq Adj pushbutton in conjunction with the (+) or (-) SENSITIVITY pushbuttons to adjust frequency.

The AT Pro is capable of operating at four slightly different frequencies in order to minimize the interference caused by electrical sources (e.g. power lines) or other metal detectors.

To adjust frequencies, hold down the PINPOINT button and press the (+) or (-) SENSITIVITY pushbuttons to change the frequency to find one with the least amount of interference.

The frequency setting (F1–F4) will be indicated on the LCD.

Release the PINPOINT button when finished.

Note: Frequency adjustments are small and therefore do not affect target detection capabilities.


PINPOINTING

Press and hold the Pinpoint pushbutton to determine

the exact location of a target. To use the pinpoint function, position the searchcoil to the side of the target's suspected location at a fixed height above the ground (e.g. 2cm). Press and hold the Pinpoint button and sweep the searchcoil over the target area while maintaining the same fixed height above the ground (e.g. 2cm). Sweep the searchcoil sideto-side and front-to-back in a crosshair pattern to locate the peak signal. Note: it is recommended to maintain a constant height during the entire Pinpointing process to prevent ground mineralization from producing false signals or masking the target's signal.

The bar graph on the LCD can also aid in locating the peak signal. When pinpointing, the Upper Scale on the LCD Screen indicates signal strength. When the greatest number of LCD segments (increasing left to right) are shown, the center of the searchcoil is directly over the target with the depth of a coin-sized target shown on the depth scale. The symbol "PP" for pinpoint is displayed on the LCD while pinpointing.

It is recommended to practice pinpointing in a test plot.

Note: The center of detection is under the center of the coil, just ahead of its stem mount. The opening just ahead of the stem mount can serve as your reference point for pinpointing.

Indicates pinpointing center of the

28 x 22 cm DD searchcoil.


Traditional pinpointing technique using Pinpoint pushbutton.

Upper Scale indicates signal strength

Coin Depth

Indicator

PINPOINT Pushbutton

(Press and hold to pinpoint)

Note: For best pinpointing results, maintain a constant height above the ground (e.g. 2cm) and ensure that the detector is properly ground balanced.


Tip for narrowing the detection area: Large targets can produce wide signals while pinpointing, making it difficult to precisely locate the target's center. To help pinpoint, the detector can be retuned to the target to narrow the detection field as follows.

While holding down the Pinpoint pushbutton, move the coil toward the target until the LCD just reaches a full-scale response. Then, quickly release and depress the Pinpoint button again to retune the detector and narrow its detection field. Continue moving the searchcoil toward the target to find its central peak response. If needed, repeat the retune process to further narrow the target's response.

5-10cm

A quality hand-held pinpointer such as Garrett's Pro-

Pointer is a recommended accessory item to speed the target recovery process and to aid in locating secondary targets.

Coin Depth Indicator—The depth of a coin, or similar sized target, is indicated in 5cm increments. Note: targets larger than a coin may display shallower than actual depth while targets smaller than a coin may display deeper than actual depth.


• Alternative pinpointing technique: DD-tip or tail. In the standard pinpointing method described on pages 34, the target is pinpointed beneath the center of the searchcoil.

Some detectorists using DD coils prefer to pinpoint off the tip or tail of the searchcoil.

Image A

DD "tip" pinpointing technique

Press and hold the Pinpoint pushbutton and sweep the searchcoil side-to-side to center the target (the point where the strongest audio response is heard and the maximum signal strength is displayed on the LCD).

Then, pull the searchcoil slowly toward you (see Image A), while noting the target signal.

PULL COIL TOWARD YOU

Image B Once the target signal drops off

(both audibly and on the LCD meter), shallow targets should be located immediately in front of the searchcoil's tip (see Image

B). Deep targets will be under or just inside your searchcoil's tip.

This is because the conical shape of the searchcoil's detection field begins bending in slightly as the depth increases.


You can reverse this pinpointing technique to pinpoint off the DD coil's tail; in this case, push the coil away from you.

The audio and LCD meter will place the target just off the searchcoil's tail.

• Alternative pinpointing technique: DD-wiggle. Quickly locate targets without using the Pinpoint button as follows.

Continuously swing the searchcoil side-to-side using fast, narrow swings of 5–10cm (i.e. wiggle). While continuing this side-to-side wiggle, slowly move the searchcoil sideways toward the target's suspected position until the audio response produces a consistent, symmetric beat. This indicates the lateral left-to-right position of the target. Then locate the target's front-to-back position by rotating around 90° and repeating the same process.

Tip: Practice any or all of these various pinpointing options in your test plot. Choose the technique that works best for you.

As you improve your pinpointing accuracy, you will dig smaller holes and increase your productive hunting time.

HUNTING TIPS

• Begin hunting in STD Mode, then switch to PRO Mode after

you have become more experienced.

• If you are new to metal detecting, start searching in areas

with sandy and loose soil to make it easier to learn how to

use your metal detector, pinpoint and dig targets.

• Keep your searchcoil at a constant height of 2 to 3 cm

above and parallel to the ground at all times for best

detection results. Do not lift or tilt the coil at the end of

swings.

CORRECT

SWING


INCORRECT

SWING



Walk slowly to allow overlapping of the searchcoil

Scan side to side approx.

1m per second.

• Walk slowly as you scan your searchcoil in a straight line

from side to side at a speed of about 1 meter per second.

Advance the searchcoil about half the length of the

searchcoil at the end of each sweep.

Overlap Swing by 14 cm

1m/sec

1m/sec

Overlap Swing by 14 cm

1m/sec

In order to fully search an area, overlap the swings of your searchcoil by half the length of the coil (about 14 cm). Sweep the searchcoil in a straight line or with a slight arc at a sweep speed of about 1m/sec.

Tips for saltwater use: Hunting in a saltwater environment is challenging for any Continous Wave (VLF) metal detector.

Saltwater is conductive and produces signals similar to foil.

Although the AT Pro is not specifically designed for saltwater use, it can be used in this environment.

Proper ground balance is the most important step for stable saltwater operation. To achieve stable operation:

• First, Ground Balance the detector to the area that will

be hunted (see pages 31–32). Saltwater beaches

typically Ground Balance between 0 and 20.

• If necessary, reduce the Sensitivity until the signals

become stable.

• Swing the searchcoil flat and at a constant height.

Do not bounce the coil or lift the coil at end of swings.

• Swing the searchcoil parallel to the water's edge.


• The detector will be less stable in shallow, breaking surf

where the searchcoil is in and out of the saltwater.

In this area the detector is encountering a constantly

changing environment produced by the surf, making it

difficult for the detector to stabilize.

To improve stability, negatively bias the ground

balance by several points. To do so, simply press

and release the Ground Balance button and

use the (-) NOTCH DISC pushbutton to manually reduce

the ground balance setting. For example, if the Ground

Balance number was 11, reduce the Ground

Balance number to 7 or 8. Introduce only

enough negative bias to achieve sufficiently stable

operation. Reduce the detector's Sensitivity as needed.

Note: While some background chatter may remain, the

more definitive response of a target can be recognized.

• If necessary, notch out the first pixel under Foil. It is

important to note that by notching out this pixel,

detection of some small jewelry items will be reduced.

Tips for locating targets amongst terra cotta/hot rocks:

Magnetic minerals such as hot rocks and terra cotta can mask the presence of good targets. In order to detect a good target, first ground balance the AT Pro to the terra cotta or hot rocks that are present. Be aware, however, that the combined

Target ID might be very low (e.g. a bronze coin and terra cotta together may register between 10 and 15 on the Digital

Target ID). Therefore, Iron Discrimination levels must be reduced in order to ensure detection of good targets covered by the terra cotta. The Iron Audio feature can also be used so that all targets above the point of discrimination produce either a medium or high tone (i.e. "good" targets).


• Isolating adjacent targets. The narrow detection field of the AT Pro's DD searchcoil allows better separation of adjacent targets versus a similar size concentric searchcoil.

Use narrow swings of the searchcoil in trashy areas to isolate good targets amongst the trash.

DD

Searchcoil

Concentric

Searchcoil

• Swing your searchcoil parallel to plow lines and the water's edge.

This will minimize the negative effects caused by uneven ground in plowed fields and varying amounts of moisture near the water. Do not swing the searchcoil perpendicular to plow lines and the water's edge, as this may produce abrupt changes in ground response that can reduce the detector's performance.


BENCH TESTS

You should conduct bench tests to become more familiar with the AT Pro’s operation in both Standard and PRO modes.

In addition, the use of the Iron Audio feature should be tested in both Standard and PRO modes. Suggested test items should include:

• Coins

• Iron nail

• Bottle cap or steel washer

To conduct a bench test, place the searchcoil on a flat, non-metallic surface that is several feet from other metallic objects. Begin by testing in the STD Mode with the ZERO discrimination pattern. Pass the coins individually across the searchcoil at a distance of 8 to 10 cm. Listen to the audio tone that the detector produces for each coin while also observing the Target ID for each. Next, select the PRO Mode

For bench testing, place the searchcoil on a flat, stable, non-metallic surface that is several feet from other metallic objects.

44 Garrett Metal Detectors with ZERO discrimination and pass the same coins across the searchcoil. Observe the sounds as well as the Target ID as each target is tested.

The proportional audio characteristics of the PRO Mode can be easily understood using such bench testing. Pass the coins across the searchcoil at distances that vary from 5 cm to 10 cm to 15 cm. In STD Modes, the test targets will produce a consistent, full-strength tone regardless of their distance from the coil.

Discrimination bench test: A similar test procedure can be used to better understand how to set discrimination levels and the AT Pro’s advanced audio characteristics. Begin by testing the iron nail in the STD and PRO Modes with the

ZERO discrimination pattern. Listen to the Low-Tone sound an iron object creates and note the Digital Target ID number it produces.

If the iron nail registers up to a 26 on the Digital

Target ID, use the IRON DISC pushbuttons to move the Iron

Discrimination setting up to 26. Pass the iron nail across the searchcoil again to verify that it has been eliminated. If not, raise the Iron Discrimination setting a little higher using the (+) IRON DISC touchpad until the iron target no longer produces an audible response.

Next, press the IRON AUDIO pushbutton and pass the iron nail across the searchcoil again. Test this target both in STD and PRO Modes with the Iron Audio feature switched on.

Iron Audio bench test: Flat iron objects like bottle caps or steel washers can appear to be good conductive targets to detectors operating in the standard mode. To better understand the benefits of Iron Audio, use a bottle cap to test the AT Pro's advanced audio features.

First, set the detector to Standard Mode with Zero discrimination and pass the bottle cap across the searchcoil


at a distance of 8 to 10 cm. Note that the bottle cap's flat surface gives a Digital Target ID reading in the 75–85 range and produces the high tone of a "good" target.

Next, switch to PRO Mode and pass the bottle cap across the coil again and notice the different audio. The clean sound heard in STD has been replaced with a mixed, chirping tone that has subtle low tones at the beginning and end, indicating a possible junk target. Pass a conductive, coin-sized target across the coil and note its clean high tone in comparison to that of the bottle cap.

Finally, remain in PRO Mode and set IRON DISC to 35 and switch on the Iron Audio feature. Pass the bottle cap completely across the coil again and note the high-tone chirp that is flanked by distinctive low tones on either side. Again, use a conductive, coin-sized target to compare its signature to that of a bottle cap in this PRO Mode Iron Audio setting.

The bottle cap makes a response that is unmistakably iron.

Final tip: Record the results of your bench tests and refer to them when hunting in the field. Knowledge of the PRO

Mode and the Iron Audio feature can reduce the amount of trash targets that are dug.

UNDERWATER OPERATION

The

(maximum) to search in and along shorelines, rivers, piers, docks or swimming holes. Use of the AT Pro at depths exceeding 3 meters can cause leaks and damage the detector. Use of the AT Pro beyond the recommended depth will void the manufacturer's warranty. For use in saltwater, see tips on pages 41–42.

AT Pro is shipped with standard land-use headphones.

These can be used for searching along waterways, but may not be submerged. For submersion, optional waterproof headphones (available from Garrett) must be used.


Waterproof headphones (sold separately) must be used if the AT Pro is fully immersed in water. The standard land-use headphones included with the detector are not waterproof.


CARE AND MAINTENANCE

Battery Level

Indicator

Battery Replacement —The AT Pro is operating with fresh or fully charged batteries when 4 illuminated bars on the

Battery Level Indicator (see above) are displayed. The detector will maintain full performance until the batteries need to be replaced. Replace batteries when there is only

Remove the battery cover by rotating the cover onequarter turn in a counterclockwise direction. Grasp the cap by top and bottom and pull it straight back. Slide the battery tray out to replace the batteries.

INSERT BATTERY HOLDER

IN THIS POLARITY

48 Garrett Metal Detectors one segment remaining. NiMH rechargeable batteries may be used. Expect 20 to 40 hours of operation depending on battery type and quality.

Access and replace the batteries by rotating the battery cover housing one-quarter turn counterclockwise. Pull and remove the cap to slide battery holder out. Remove batteries when the AT Pro will be stored for longer than 30 days.

The AT Pro is a rugged machine, designed for outdoor use in all environments. However, as with all electronic equipment, there are some simple ways to care for the detector to maintain its high performance.

• Avoid extreme temperatures as much as possible, such

as storing the detector in an automobile trunk during the

summer or outdoors in sub-freezing weather.

• Keep the detector clean. Wipe the control housing with a

damp cloth when necessary.

• Disassemble the stem, and wipe it and the searchcoil clean

with a damp cloth.

• When storing for longer than one month, remove the

batteries from the detector.

• It is best to use quality alkaline batteries. When changing

batteries, be sure to replace with all new batteries for

optimum performance.

• Replace protective cover on the connector when not using

headphones.


TROUBLESHOOTING GUIDE

SYMPTOM

No power

Erratic sounds or target ID cursor movement

Intermittent Signals

I’m not finding specific targets

Target ID Cursor bounces

SOLUTION

1. Ensure batteries are installed in the correct position.

2. Replace all old batteries with all new batteries.

1. Ensure your searchcoil is securely connected with the

O-ring properly sealed and that the coil cable is snugly

wound around the stem.

2. If using the detector indoors, be aware that excessive

amounts of electrical interference exists, plus excessive

amounts of metal can be found in floors and walls.

3. Determine if you are close to other metal detectors or other

metal structures such as electrical power lines, wire fences,

benches, etc.

4. Adjust frequency.

5. Reduce your sensitivity setting.

Intermittent signals typically mean you’ve found a deeply buried target or one that is positioned at a difficult angle for your detector to read. Scan from different directions to help define the signal. In the case of multiple targets switch to the

ZERO Mode or press the pinpoint button to precisely locate all targets. In trashy areas, use the Super Sniper™ searchcoil.

(NOTE: Iron targets may cause Intermittent Signals. You can identify iron targets in ZERO Mode or with the Iron Audio feature).

Ensure you are using the correct mode for the type hunting you are doing. If specifically hunting for coins, COINS mode should be your best choice to eliminate other undesirable targets. You may also use the ZERO mode, which detects all metal targets to ensure desired targets are detected.

If your Target ID Cursor bounces erratically, chances are you’ve found an iron target. However, a Target ID Cursor may bounce if a good target (such as a coin) is not parallel to the searchcoil (e.g. on edge). It may also bounce if there is one or multiple “junk” targets laying next to the good target. Scan from different directions until your Target ID Cursor becomes more stable.

NOTE: Large, flat pieces of iron—depending on their orientation in the ground—can read as a good target or can cause erratic Target ID Cursor movement. Use Iron Audio feature to help identify iron targets.


METAL DETECTING CODE OF ETHICS

The following is a Code of Ethics that many treasure hunt clubs endorse and hobbyists follow to preserve our exciting hobby of metal detecting. We encourage you to do the same:

• I will respect private and public property, all historical and

archaeological sites and will do no metal detecting on

these lands without proper permission.

• I will keep informed on and obey all local and national

European legislation relating to the discovery and reporting

of found treasures.

• I will aid law enforcement officials whenever possible.

• I will cause no willful damage to property of any kind,

including fences, signs and buildings.

• I will always fill the holes I dig.

• I will not destroy property, buildings or the remains of

deserted structures.

• I will not leave litter or other discarded junk items lying

around.

• I will carry all rubbish and dug targets with me when I leave

each search area.

• I will observe the Golden Rule, using good outdoor manners

and conducting myself at all times in a manner which will

add to the stature and public image of all people engaged

in the field of metal detection.


CAUTIONS

When searching for treasure with your Garrett detector, observe these precautions:

• Never trespass or hunt on private property without

permission.

• Avoid areas where pipelines or electric lines may be

buried.

• National and state parks / monuments, etc are absolutely

off-limits.

• Deepseeking detectors can detect concealed pipes, wiring

and other potentially dangerous material. When those are

located, the proper authorities should be notified.

• Do not hunt in a military zone where bombs or other

explosives may be buried.

• Do not disturb any pipeline, particularly if it could be

carrying flammable gas or liquid.

• Use reasonable caution in digging toward any target,

particularly in areas where you are uncertain of the ground

conditions.

• If you are unsure about using your metal detector in any

area, always seek permission from the proper authorities.


WARRANTY & SERVICE

parts and labor, but does not cover damage caused by alteration, modification, neglect, accident or misuse. Use of the AT Pro at submerged depths exceeding 3 meters will void this warranty.

In the event you encounter problems with your AT Pro detector please read through this Owner’s Manual carefully to ensure the detector is not inoperable due to misadjustments.

Press and hold the power pushbutton for 5 seconds to return to the factory settings.

You should also make certain you have:

1. Checked your batteries, switches and connectors. Weak batteries are the most common cause of detector problems.

2. Contacted your dealer for help, particularly if you are not familiar with the AT Pro detector.

In the event that repairs or warranty service are necessary for your AT Pro, contact the local retail outlet where your detector was purchased. To avoid excessive shipping and import charges, do not attempt to return a Garrett product to the factory in the United States.

Information on international warranty/repair needs can be found on the Garrett website: www.garrett.com. Click on the

Hobby Division and then the Technical Support page for more details.


AT Pro ACCESSORIES

11.5cm Super Sniper ™ Searchcoil—

Part No. 2222500

Use when searching for small, shallow targets or in trashy or tight places.

23 cm. PROformance Concentric Searchcoil—

Part No. 2222600

Smaller and lighter than the AT Pro's standard DD coil, this waterproof searchcoil offers excellent depth for medium-sized targets in less mineralized soils.

30.5 cm. PROformance Concentric Searchcoil—

Part No. 2222700

This larger size concentric searchcoil is waterproof and offers excellent depth for larger targets in less mineralized soils.

Waterproof Headphones—

Part No. 2202100

Required when the entire headphone set will be immersed in water.


28 cm. DD Searchcoil Cover—

Part No. 1606600

Protect the searchcoil's surface from scratching and chipping during use.

Garrett ® Pinpointing Detector—

Part No. 1166000

The PRO-POINTER combines performance with sleek design to assist in pinpointing hard-to-find targets. Includes proportional audio/vibration pulse rate target indicators and 360° side scan detection area. Water resistant with LED light for low light uses.

Includes woven belt holster and 9-volt battery.

To see Garrett's complete collection of metal detector accessories, please visit www.garrett.com and view products within our Hobby

Division.

Additional searchcoils, recovery tools, headphones, carrying bags, searchcoil covers, Garrett caps and Garrett shirts are available for all detecting accessory needs.


SUGGESTED READING

Also available—pocket size treasurehunting field guides written by

Charles Garrett. Collect them all!

This edition includes the author's personal experiences of hunting in Europe, plus tips and techniques. 76 pages. PN 1546200

Author/master treasure hunter

RAM BOOKS TITLES

RAM Books, a division of Garrett Metal Detectors, publishes new titles each year related to treasure hunting, gold prospecting, coin hunting and relic recovery.

Suggested

Reading:

European Metal

Detecting Guide

Highlights include:

• Hundreds of full-color photographs

• 5.5” x 8.5” size

• 324 pages, soft cover

Part No. 1562100

• Field tips from dozens of European

metal detectorists

• Explanation of detector and

searchcoil technology

• Illustrations of proper detector

techniques

• European treasure laws information

Ideal reading for new detectorists!

(Available in English language only)

Visit RAM Books on www.garrett.com for future releases.


European Metal Detecting Guide

Preview of Pages

Dozens of pages of fullcolor treasure photos with descriptions of the items’ age or value.

Photo exposes from the field, such as this

French rally experience. 

 Proper basic search techniques with illustrations.

TO VIEW OTHER RAM BOOKS:

Go to www.garrett.com and visit the Hobby Division. An order form is available on our site which can be printed and mailed with your requested titles and payment.


1881 W. State Street

Garland, Texas 75042

Toll Free: 800.527.4011

Tel: 972.494.6151

Fax: 972.494.1881

Email: [email protected]

© 2012 Garrett Electronics, Inc.

PN 1533300.C.1012

GARRETT AT Pro™ International, Owner's Manual

The powerful, all-terrain solution for locating deeply buried European coins and artefacts!

Owner’s Manual

THANK YOU FOR CHOOSING

GARRETT METAL DETECTORS!

TABLE OF CONTENTS

AT Pro CONTROL PANEL

QUICK START GUIDE

AT Pro COMPONENTS

LIST OF PARTS

ASSEMBLY

POWERING ON

SEARCH MODES

TARGET ID INFORMATION

DIGITAL TARGET ID

TONE ID

DISCRIMINATION

IRON AUDIO

SENSITIVITY

GROUND BALANCE

FREQUENCY ADJUSTMENT

PINPOINTING

HUNTING TIPS

CORRECT

SWING

INCORRECT

SWING

BENCH TESTS

UNDERWATER OPERATION

CARE AND MAINTENANCE

TROUBLESHOOTING GUIDE

METAL DETECTING CODE OF ETHICS

CAUTIONS

WARRANTY & SERVICE

AT Pro ACCESSORIES

SUGGESTED READING

Also available—pocket size treasurehunting field guides written by

Charles Garrett. Collect them all!

RAM BOOKS TITLES

Suggested

Reading:

European Metal

Detecting Guide

Visit RAM Books on www.garrett.com for future releases.

European Metal Detecting Guide

Preview of Pages

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Table of contents