Garrett AT Gold User manual

© 2011 Garrett Electronics, Inc. PN 1533500.A.0811
1881 W. State Street
Garland, Texas 75042
Tel: [phone]
Email: [email protected]
Fax: [phone]
AT GOLD Owner’s Manual
Owner’s Manual
Deep-seeking True All Metal Mode Performance
for All Terrain Prospecting!

AT Gold™1
THANK YOU FOR CHOOSING
GARRETT METAL DETECTORS!
Congratulations on the purchase of your new Garrett
AT Gold™metal detector. It was designed to find tiny gold
nuggets in the most challenging prospecting environments,
including shallow fresh water hunting.
The AT Gold operates at a high frequency optimized for
gold prospecting and includes a True All Metal Mode. The ALL
METAL Mode is preferred for prospecting because it provides
the greatest possible depth and sensitivity. It also provides a
continuous audio response to allow the operator to hear the
subtle detection signals produced by faint targets.
The AT Gold is a Motion All Metal detector, meaning
that slight motion of the searchcoil is required to maintain
detection, although static detection of targets can be
achieved while in Pinpoint mode. The AT Gold includes
manual and automatic Ground Balance—plus an exclusive
Ground Balance Window™ feature—to optimize the detector's
performance in highly mineralized ground, where gold is most
often found. This detector is also waterproof to a maximum
depth of 10 feet (3 meters) for searching in freshwater lakes
and streams.
In addition to its True All Metal Mode, the AT Gold includes
two Discrimination Modes, making it a versatile coin and relic
hunting machine. When selecting either the DISC 1 or DISC
2 mode, the operator gains more Tone ID information from
targets in addition to the ability to discriminate unwanted
trash targets (e.g. nails, foil, pull tabs).
The AT Gold also features simple, one-handed operation
for all controls—no dials or knobs that require a second hand
to adjust.

2Garrett Metal Detectors AT Gold™3
TABLE OF CONTENTS
AT GOLD CONTROL PANEL........................................................................................4
QUICK START GUIDE..................................................................................................5
AT GOLD COMPONENTS ...........................................................................................6
LIST OF PARTS ...........................................................................................................7
ASSEMBLY .................................................................................................................8
POWERING ON.........................................................................................................11
TARGET INFORMATION........................................................................................... 12
DIGITAL TARGET ID ..................................................................................................13
SENSITIVITY.............................................................................................................15
GROUND BALANCE..................................................................................................16
Automatic Ground Balance..............................................................................17
Manual Ground Balance..................................................................................17
Adjustable Ground Balance Window...............................................................18
FREQUENCY ADJUSTMENT .....................................................................................21
THRESHOLD ADJUSTMENT.................................................................................... 22
SEARCH MODES OVERVIEW .................................................................................. 23
ALL METAL MODE....................................................................................................24
ALL METAL Mode Overview..............................................................................24
Audio Characteristics of ALL METAL Mode .................................................... 25
DISCRIMINATION MODES ...................................................................................... 26
DISC Modes Overview..................................................................................... 26
Tone ID in DISC Modes ................................................................................... 26
Audio Characteristics of DISC Modes .............................................................27
DISC 1 Mode (Zero Discrimination Pattern) ...................................................27
DISC 2 Mode (U.S. Coins Discrimination Pattern)......................................... 28
IRON DISCRIMINATION........................................................................................... 29
IRON AUDIO ............................................................................................................ 32
Iron Audio Use in DISC Modes
........................................................................ 32
Tip for Using Iron Audio................................................................................... 34
Iron Audio Use in ALL METAL Mode ............................................................... 35
AUDIO CHARACTERISTICS...................................................................................... 36
Proportional Audio Target Examples...............................................................37
BENCH TESTS......................................................................................................... 38
SWEEPING THE SEARCHCOIL.................................................................................41
PINPOINTING .......................................................................................................... 43
Tip for Narrowing the Detection Area............................................................. 45
Alternative Pinpointing Techniques................................................................ 46
ADVANCED TIPS AND TECHNIQUES ...................................................................... 48
PROSPECTING TIPS................................................................................................ 52
UNDERWATER OPERATION .................................................................................... 54
CARE AND MAINTENANCE ..................................................................................... 56
Battery Replacement ...................................................................................... 56
TROUBLESHOOTING GUIDE ................................................................................... 58
METAL DETECTING CODE OF ETHICS ................................................................... 59
CAUTIONS ............................................................................................................... 60
WARRANTY / SERVICE ............................................................................................61
ACCESSORIES......................................................................................................... 62
SUGGESTED READING........................................................................................... 64
Garrett's exclusive Target ID technology provides two
indicator scales which allow you to see the detector’s
discrimination setting (Lower Scale) as well as the analysis
of each target (Upper Scale). In addition, the Digital Target
ID provides a more specific target value. The AT Gold also
features High Resolution Iron Discrimination (40 points)
for separating desirable targets from iron junk, several
advanced audio features, and a standard 5"x8" (13x20cm)
DD searchcoil optimized for detecting small nuggets in
challenging mineralized soils.
Backed by more than 45 years of extensive research and
development, your Garrett AT Gold metal detector is the most
advanced of its kind in the industry. The AT Gold's advanced
audio features are designed for the serious prospector but will
also prove to be very appealing to coin and relic hunters.
In order to take full advantage of the special features and
functions of the AT Gold, you are urged to carefully read this
instruction manual in its entirety.

4Garrett Metal Detectors AT Gold™5
AT GOLD CONTROL PANEL QUICK START GUIDE
1. Install batteries.
The AT Gold operates with four (4) AA batteries which are
already installed by Garrett.
2. Power ON.
Press and release the ON / OFF Power button. The AT Gold
powers on in the last mode used and is ready to search.
(Factory default mode is ALL METAL.)
3. Select Mode.
Use the Mode Pushbutton to select a different detection
mode, if desired.
4. Adjust settings.
Adjust Sensitivity or Discrimination settings, if desired.
5. Begin scanning.
Lower the searchcoil to within 1" (2.5cm) of the ground and
scan the coil left and right at approximately 3 feet (1m)
per second.
Battery Level
Indicator
FREQ
Pushbutton
to toggle through
4 frequencies.
SENSITIVITY
Pushbutton
to change sensitivity .
ON / OFF Power: hold 1 second
to turn power on/off.
MODE: press quickly to toggle
through detection modes .
RESET: hold 5 seconds to restore
factory settings.
Depth Indicator
indicates depth of a
coin-sized target .
Mode
Indicator
Target ID
Legend
indicates
metal types.
Lower Scale
indicates notch
discrimination pattern.
Target ID
Cursor
indicates
probable
target identity.
Digital
Target ID
(also shows
ground balance
settings while in
GND-BAL mode.)
PINPOINT
Pushbutton
Press and hold
to pinpoint.
Sensitivity
Setting
High Resolution
Iron Discrimination
indicates level of iron
discrimination selected.
Iron Disc
Pushbutton
to change iron
discrimination level.
Iron Audio
Pushbutton
to toggle Iron
Audio ON/OFF.
GROUND BALANCE
Pushbutton
Press and hold for fast auto
ground balance or use with
THRESHOLD (+) or (-) for
manual ground balance.
THRESHOLD Pushbutton
to change the level of
background sound .

6Garrett Metal Detectors AT Gold™7
AT GOLD COMPONENTS
Control
Housing
S-shaped
Stem
Middle
Stem
Lower
Stem
Search
coil
Handle
Grip
Padded
Arm Cuff
LCD
Screen
Detector
Stand
Pushbutton
Controls
Arm
strap
Camlocks
nOne (1) control housing with
S-shaped stem
oOne (1) upper stem and one
(1) lower stem connected,
with camlock fasteners
pOne (1) wing nut, two (2)
mounting washers and
one (1) threaded bolt
qOne (1) 5"x8" (13x20 cm)
DD searchcoil
rOwner's manual
sWarranty Card
tHeadphones
n
o
ps
r
q
LIST OF PARTS
No tools are required to assemble the AT Gold. Four (4) AA
batteries are included with the detector. The box for your
detector contains the following parts:
t
If any part is missing, please contact your local dealer.

8Garrett Metal Detectors AT Gold™9
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.
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!
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.
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.
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.
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.
1. 2. 3.
4. 5. 6.
7. 8. 1st pin position
9. 10.
11.

10 Garrett Metal Detectors AT Gold™11
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.
POWERING ON
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 seconds (until the detector produces a fast
double beep).
ON/OFF Power
and MODE
Pushbutton
12.
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
61 for optional waterproof headphones.
13.
14.

12 Garrett Metal Detectors AT Gold™13
TARGET INFORMATION
Target ID Cursor
(Upper Scale)
Target ID Legend 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 gold) 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 Gold 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.
Depth Indicator—The depth of a coin, or similar sized
target, is indicated in 2" (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.
DIGITAL TARGET ID
Digital
Target
ID
The AT Gold’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 large
gold and 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 47 will light the cursor from 45 to 50.
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 detection depth can exceed
Target ID depth (i.e. faint targets at depth can be heard
without providing any Target ID).
Target ID
Cursor
Depth
Indicator

14 Garrett Metal Detectors AT Gold™15
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.
The Digital Target ID for gold and other conductors can
vary widely based upon its size and thickness. This is because
small, thin pieces of metal cannot conduct electrical current as
well as thicker pieces of metal. Therefore, small, thin gold—for
example—will register lower on the Target ID scale than would
a larger, thicker piece of gold, even if the two pieces have
identical purity. In addition, in mineralized soils, the Target ID of
small gold pieces can be skewed by the ground mineralization
into numeric IDs that normally indicate iron. Most small gold
nuggets indicate in the 40 to 60 range. Very tiny nuggets and
deeply buried targets with small signal response may not give
a numeric reading at all. Nevertheless, targets which do not
give any Target ID are often worth investigating.
Tips: Digital Target ID is most reliable when the target
is properly pinpointed and centered under the searchcoil
and the coil is swept flat and at a constant height above the
ground. Use a magnet to help remove small bits of shallow
iron and then scan over the area again to see if the Target ID
has changed.
SENSITIVITY
SENSITIVITY
Pushbutton Sensitivity
Indicator
The AT Gold 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, electrical interference
or the presence of other metal detectors) and the erratic
operation cannot be resolved with discrimination, ground
balance, or by changing frequency.
Silver
$1
Silver
$1
10¢10¢
1¢1¢ 25¢25¢
5¢5¢
ThinThin ThickThick
0 10 20 30 40 50 60 70 80 90 99
Iron, Steel
Iron, Steel
FoilFoil
Gold nuggets, silver, copper
bronze, larger jewelry
Gold nuggets, silver, copper
bronze, larger jewelry
Lead Projectiles
Lead Projectiles
Pull-
tabs
Pull-
tabs
Tiny gold,
small jewelry
Tiny gold,
small jewelry
DIGITAL TARGET ID

16 Garrett Metal Detectors AT Gold™17
GROUND BALANCE
GND BAL
Pushbutton
THRESHOLD
Pushbutton
(use with GND BAL)
GND BAL Pushbutton—Hold for Automatic Ground Balance
or use in conjunction with the THRESHOLD pushbuttons for
Manual Ground Balance. The Ground Balance setting will be
retained when the detector is switched OFF.
As ground mineralization begins to increase, it has a
negative affect on detector performance. The greater the
amount of mineralization, the greater the loss of detection
depth and Target ID accuracy becomes. It is imperative to
ground balance the detector to maintain optimal performance.
The AT Gold can be ground balanced either automatically
or manually to cancel unwanted ground signals and obtain
maximum stability and target detection. By calibrating the AT
Gold's ground balance to the phase (measurement) of the
GND BAL
Indicator
(only displays
while in Ground
Balance mode)
GND BAL Setting
(only displays
while in Ground
Balance mode)
ground's signal, the result is deeper target detection, more
accurate Target ID, and more stable operation.
Note: Always locate an area of soil free of metal before
attempting to ground balance the detector.
Automatic Ground Balance—Press and hold the GND BAL
pushbutton while continually "bouncing" or "pumping" the
searchcoil from 1 to 8 inches (2 to 20 cm) 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.
Note: If the AT Gold's Ground Balance setting does not
change during the auto ground balancing process, the
detector is either sufficiently ground balanced already or the
current ground exhibits such neutral mineralization that the
settings will not change.
Manual Ground Balance—Press and release the GND BAL
pushbutton and continually bounce (pump) the searchcoil
from 1 to 8 inches (2 to 20 cm) above the ground. If low tones
are produced, increase the Ground Balance setting using
the (+) THRESHOLD pushbutton. If high tones are produced,
decrease the setting using the (-) THRESHOLD pushbutton.
Press and release the (+) or (-) THRESHOLD 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.