Fisher Labs 1280-X Aquanaut User manual

1280-X Aquanaut
Operating Manual
Automatic Metal Detector for Sea, Surf or Shore
FISHER RESEARCH LABORATORY

CONTENTS
About Your 1280-X .................................................................pg. 1
Assembly ................................................................................pg. 2
Setting Up................................................................................pg. 3
Hipmounting........................................................................... pg. 5
Control Panel ......................................................................... pg. 7
Discrimination Points ............................................................. pg. 8
Searching ...............................................................................pg. 10
Pinpointing.............................................................................. pg. 12
Target Recovery ....................................................................pg. 13
Recovery Tools ...................................................................... pg. 15
Operating Tips........................................................................pg. 17
Sinker Assembly ....................................................................pg. 17
Battery Replacement............................................................ pg. 18
Battery Recharging ............................................................... pg. 18
Maintenance .........................................................................pg. 20
Search Coils ...........................................................................pg. 21
Treasure Hunter’s Code of Ethics .........................................pg. 21
Where to Hunt in the U.S........................................................ pg. 22
Specifications ........................................................................pg. 23

ABOUT YOUR DETECTOR
1
Fisher Research Laboratory has been producing rugged, high
quality, high performance metal detectors since 1931, longer
than any other company in the world. Your 1280-X Aquanaut is a
product of that proud heritage. Designed for deep sea treasure
hunting, the 1280-X will also do the job in fresh water or on land.
The 1280-X is easy to use. No fine tuning, no threshold tone
and no complicated “ground-adjustment”. Just turn it on, set the
volume, sensitivity and trash discrimination controls, and you
probably won’t have to touch the knobs again. The 1280-X
automatically tunes itself to changing ground conditions and salt
water, rejects most small pieces of junk and detects valuable
targets all at the same time.
The 1280-X is built to take a beating. The search coil is light-
weight glass-bead epoxy filled. The shaft is fiberglass reinforced
ABS. The control housing is injection molded ABS. The state-of-
the-art Piezo Electric headset was designed especially for the
1280-X. And the entire unit is submersible to 250 feet.
The 1280-X is a “motion” detector, meaning the search coil
must be in motion to detect a target. However, the motion
required is slight and unlike earlier “motion” detectors, you’ll be
able to almost completely stop the coil for accurate pinpointing.
Your 1280-X is a precision metal detector designed and
manufactured by the oldest and proudest name in the business.
Take good care of it, read this instruction manual carefully and
you’re in for some exciting treasure hunting. If you have any
questions, suggestions or make any big finds, drop us a line. We
want to hear from you. In the meantime...
Happy Hunting!
Fisher Research Laboratory

2
ASSEMBLY
The 1280-X requires very little assembly. Unpack it carefully and
save the carton which may come in handy for future storage or
shipment. 1. Remove the headphone, handle and search coil
assemblies from the shipping carton. Be careful not
to damage the foam rubber inserts or put any strain
on the cable connections.
2. Adjust the stem to the approximate length you
will be using, extended for stand-up use or, as short
as possible for diving. To extend the lower stem,
push in the spring lock, pull out the lower stem and
let the spring lock snap into another hole.
3. If you will be using the 1280-X on the handle, and
not body mounted, wind the search coil cable
around the handle assembly as shown in the
diagram above. Secure the cable with the two
Velcro straps included with your 1280-X. Make sure
there is some slack at the control housing end and
enough slack at the other end to attach the search
coil.
4. Remove the Delrin bolt and nylon wing nut from
the search coil. Line up the hole in the stem
between the two holes in the search coil “ears”.
Attach the coil to the stem with the bolt and wing
nut and finger tighten.
Derlin Screw and
Nylon Wing Nut
Arm Rest Screws
Adjustable Arm Rest
LED (Light Emitting Diode)
Control Panel
Spring Lock (Not visible)
Upper Stem
Waterproof Headphones
Battery Access Panel
Search Coil Cable
Lower Stem
8-inch Spider Coil

3
SETTING UP
FOR LAND OR SHALLOW WATER (See Figure 2-A)
Put the headphones around your neck to keep them out of the
way while making the following adjustments.
1. Adjust the length and coil angle so that the
search coil rests flat on the ground about 6 inches
in front of and slightly to the right of your right foot
(to the left of your left foot for left handers.) Your
arm should be straight and relaxed with the handle
grip held firmly but comfortably. Remember, as you
increase the shaft length, you also increase the
strain on your wrist and arm. The 1280-X is balanced
for comfortable searching in a tight semicircle
around the front of the operator.
2. Leave enough slack in the coil cable to allow
the coil to swivel as far as it can in either direction.
The coil wing nut should be tight enough to prevent
the coil from moving.
Figure 2. Setting up. When the stem length is properly adjusted, the 1280-X
is balanced for sweeping in a tight semicircle. Always overlap your swings
by at least 50%
A. Extended stem for land
or shallow water B. Short stem for diving

4
3. You should now be able to move into your
“search” position by leaning slightly forward and
raising the search coil approximately 1 inch above
the ground. Your arm should still be straight and the
coil should be parallel to the ground, about 12
inches in front of your foot. The coil angle may have
to be slightly readjusted at this point.
FOR DIVING (see Figure 2-B on previous page)
The recommended setup for underwater use is the shortest
possible stem length with the search coil adjusted parallel to the
sea bed or lake bottom. Keep the headphones around your
neck, off your ears, while descending or ascending.
SETTING UP

5
For almost effortless treasure hunting, the control housing is
easily removed from the handle and attached to a belt clip.
“Hipmounting” the 1280-X in this manner takes half the weight
off the handle and allows the land or shallow water Treasure
Hunter to search much longer without arm fatigue.
1. Grasp the handle grip firmly with one hand and
the control housing with the other.
2. Slide the control housing off the mounting
bracket by pulling it towards you.
3. Slide the belt clip into grooves on the bottom of
the control housing. This is a snug fit and you’ll have
to bend the belt clip slightly. Make sure the narrow
end of the clip goes into the grooves first and the
short hooked side faces out.
4. Unwrap just enough of the coil cable to allow
for searching.
Figure 3. You can hipmount your 1280-X by sliding the control housing from the handle
and attaching it to your belt. This reduces the weight of the stem, creating nearly
effortless hunting.
HIPMOUNTING

6
5. Slip the control housing onto your belt, left side
for right handers, right side for left-handers.
CAUTION: Hipmounting is not recommended for underwater use.
The search coil cable may become entangled with a
submerged object, making it difficult for the diver to resurface
quickly in case of emergency.
HIPMOUNTING

7
1. POWER/VOLUME CONTROL: Turns the power on
and off. Also controls the target response volume
in the headphones. The volume control should be
set no louder than comfortable when the search
coil is passed over a large, close target.
2. DISCRIMINATION CONTROL: A full range trash
rejection control. All types of metal are detected
at the zero level and most small pieces of trash
are eliminated at the maximum level of ten.
3. LED: The clear plastic window between the
SENSITIVITY and VOLUME controls contains an LED
(Light Emitting Diode) which flashes red when a
target is detected or the batteries are being
tested.
4. BATTERY TEST/SENSITIVITY CONTROL: Checks
battery condition and controls the sensitivity to
targets. A setting of 10 gives maximum sensitivity
and is used for most treasure hunting conditions.
To check the batteries, turn the VOLUME control
to 10 and click the BATTERY TEST/SENSITIVITY control
momentarily in and out of the “Battery Test”
position. Fully charged batteries will give a loud
tone in the earphones and a bright red light in
the LED window. Weak batteries will give a faint
tone and a dim light. It’s time to replace the
batteries when the light goes out.
CONTROL PANEL
Figure 4. Control Panel

8
By adjusting the DISCRIMINATION control you will be able to
ignore (or “reject”) small pieces of metallic trash and ground
minerals while detecting valuable targets. The lowest setting at
which an object is rejected is referred to as the object’s
“discrimination point”. Discrimination points are determined by
such factors as size, shape, depth, type of metal and ground
mineralization.
1. Scatter some sample targets such as coins, pull
tabs and small pieces of foil on the ground 1 to 2
feet apart.
2. Turn the SENSITIVITY control to 9.*
3. Turn the DISCRIMINATION control to zero.
4. Put the headset on and turn the POWER ON-OFF/
VOLUME control to about 6.
5. Hold the search coil about 2 inches above and
parallel to the ground. Move it slowly over the
samples and note the sharp loud response as you
pass over each one. Keep in mind that the 1280-X
is a motion detector and responds only when the
search coil (or the target) is moving.
6. Increase the DISCRIMINATION control to a
setting of 3 and again pass over the targets.
Repeat this process at settings of 4,5,6 and so on to
10. You will note that as you increase the level of
discrimination, the 1280-X will reject some targets
and continue to respond to others. You have now
determined the discrimination points for the
rejected objects. For example, the small nail
discrimination point may be at 4 and the pull tab
discrimination point at 6.
7. Some objects such as shallow bottle caps, bent
pull tabs or trash less than 2 inches from the coil
may be difficult to reject. The 1280-X will instead
respond with a strong broken signal which will
usually disappear if the search coil is raised slightly.
(The strong signal of a good target will just get
weaker when the coil is raised.)
8. The 1280-X will remain silent when some objects
DISCRIMINATION POINTS

9
DISCRIMINATION POINTS
are rejected, however other objects may “snap,
crackle and pop” as they are rejected. This is a
perfectly normal response indicating that the
powerful discrimination circuitry is doing its job.
9. Large pieces of trash such as beer cans or jar
lids may sound like good targets no matter what
you do. With a little practice, however, you will be
able to tell the difference between a large target
and a small coin sized object.
10. The diagram below shows some of the different
target responses you may expect at different levels
of discrimination. Note that as you increase the
discrimination level, you progressively eliminate
more targets including some good ones, such as
nickels and gold rings.
*Atthemaximumsensitivitylevelof10,youmayhearsomestaticor“circuit
noise”.As ageneralrule,holdthesearchcoilintheairandsetthesensitivity
at 10. If the circuit noise is annoying, reduce the sensitivity to 8 or 9.
Figure 5. Typical 1280-X audio responses over 1 inch deep targets with
search coil sweeping 1 to 2 inches above ground.

10
SEARCHING
Good search techniques remain the same whether you’re
using your 1280-X in the desert or on the bottom of the ocean.
1. Decide how much discrimination you want to use.
a. In relatively non-trashy areas you may wish to
search at zero discrimination. In this manner, your
1280-X is at its most sensitive and will detect all
metal targets within its range. Once an object is
detected, you can increase the discrimination
level for further target identification.
b. In trashy areas, it is generally easier to search
at a higher level of discrimination (at the pull tab
discrimination point for example). This way you
will detect mostly good targets and can lower
the discrimination level for pinpointing (zero
discrimination will produce the strongest signal
on small or deep targets).
2. Search slowly and systematically, sweeping in a
tight semi-circle.
3. Keep the coil parallel to, and as close to the
ground as practical.
4. Overlap your sweeps at least 50%
5. Search in a methodical manner. Pay close
attention to where you’re going and where you’ve
been.
6. Keepthesearchcoilmovingatacomfortablerate.
Figure 6. Keep the
coil parallel and as
close to the ground
at all times

11
SEARCHING
NOTE:
Other motion detectors may require a very rapid sweep for
maximum sensitivity. If you try that with your 1280-X, you’ll actually
lose sensitivity.
1. Minimum Depth
a. Very slow or fast sweep speed.
b. Discrimination set at “10.”
2. Good Depth
a. Moderate sweep speed.
b. Discrimination set at “5.”
3. Maximum Depth
a. Moderate sweep speed.
b. Discrimination set at “0.”
4. Missed Target
Many targets within the range of
your 1225-X will not be detected
unless you closely overlap your
swings.
4
1
2
3
Figure 7. Search Coil
Detection Pattern

12
Pinpointing takes practice. The more time you spend with your
1280-X, the faster and more accurate you’ll become.
1. Once a buried target is indicated by the tell-tale
“Beep” of the 1280-X, continue moving the search
coilfromside-to-side across the target in a narrower
and narrower search pattern.
2. When you have narrowed your search pattern
as much as you can and still hear the target, stop
the search coil.
3. Now, move the coil slowly forward and then straight
back towards you a couple of times. Stop the coil over
the area where you get the loudest response.
4. Move the coil slowly left to right to left one more
time, zeroing in on the loudest target response.
5. Stop the coil over the area of loudest response
and rest it on the ground.
6. Your target should be directly below the center
of the search coil.
7. For very strong signals, you may improve your
pinpointing accuracy by adding one or more of
the following steps.
a. Lift the coil until the signal is barely heard.
b. Reduce the sensitivity level.
c. Increase the discrimination level.
d. Rest the coil on the ground and move it back
and forth very slowly.
8. For very weak signals try the following:
a. Move the coil closer to the ground.
b. Increase the sensitivity level.
c. Decrease the discrimination level.
d. Speed up the sweep rate slightly.
PINPOINTING

13
Once you have pinpointed a target, your objective is to
recover it quickly and neatly, leaving virtually no trace of your
excavation. There are almost as many ways to do this as there
are treasure hunters. Whatever works best for you is good
enough as long as you don’t break any laws or leave your search
area looking like a World War II Battlefield.
Generally speaking, beachcombers and underwater treasure
hunters do little if any damage to the environment while
recovering targets. However, if you plan to use your 1280-X on
land, your target recovery method can be very important. The
“screwdriver” and “plugging” methods described here are two
of the most important and successful.
WHICHEVER TOOL OR METHOD YOU CHOOSE, REMEMBER THAT
RESPONSIBLE TREASURE HUNTERS TAKE PRIDE IN THEIR ABILITY TO
LEAVE SOIL AND VEGETATION INTACT AND UNDAMAGED.
SCREWDRIVER METHOD
The screwdriver method of recovery is an excellent choice in
areas where knives and/or plugging are not allowed, or in dry
lawns where plugging would almost certainly result in brown,
dead spots. This method will take more practice, however the
results will be worth the extra effort.
1. Once you have located your target, gently
probe the area with a screwdriver or a dull probe
until you have pinpointed its exact location.
2. Insert the screwdriver into the ground until it just
touches your target.
3. Back the screwdriver out just a quarter of an
inch or so.
4. Rotate the screwdriver until you have made a
cone shaped hole approximately 2 to 3 inches in
diameter at the top.
5. Carefully pry out your target from the bottom of
the cone with the screwdriver.
6. Recheck the target area with your 1280-X.
7. Scrape any loose dirt back in the hole. Close it
TARGET RECOVERY

14
PLUGGING METHOD
This method of recovery is not allowed in many areas and
should never be used in dry lawns or in very hot weather. A
good rule of thumb is... “When in doubt, don’t plug”. It’s a good
way to recover deep targets however in moist soil where
plugging is allowed and when done properly.
1. Once your target has been pinpointed, lay the
1280-X down (still turned on) so that the search coil
is within easy reach but not close enough to detect
your digging tool.
2. Cut a cone shaped plug about 3 inches in
diameter and at least 3 inches deep.
NOTE: If you’re in a park or lawn maintained by a
power mower, don’t cut a cone - the mower may
pull it back up. Instead cut a deep, square, un-
pointed plug.
3. Remove the plug, being careful not to scatter
loose dirt.
4. Examine the plug and the hole for your target.
5. If the target is not readily visible, pass the plug
across the front or back of the search coil. If the
target is in the plug, you will get an immediate
response from the 1280-X.
NOTE: This procedure will be successful only if:
a. You have removed any rings, watches, etc.
b. The DISCRIMINATION level is low enough to
detect your target.
c. You move the plug as close as possible across
the search coil.
6. If the target is in the plug, carefully dissect the
plug until you have recovered it. Try not to damage
roots or disturb the surface of the plug.
7. If the target is not in the plug, check the dirt in
TARGET RECOVERY
up by inserting the screwdriver into the ground next
to the hole and pulling in towards the center. Do
this 4 to 5 times around the edge of the hole until it
is no longer visible.

15
RECOVERY TOOLS
1. Sandscoops designed especially for
beachcombers and shallow water treasure hunters
are available at many metal detector outlets.
2. Divers use a variety of recovery tools depending
on the condition of the sea bed or lake bottom. A
sturdy dive knife will suffice in packed mud or small
rocks. Most divers prefer to use their hands in loose
sand and professional treasure hunters often use
an air hose fed by a surface compressor to blow
away loose sand, gravel or mud.
3. For land recovery, a sturdy hunting knife with a
5" blade will suffice in most soils. A high quality,
double edged “survival” knife is an even better
choice (and more expensive) since it will be almost
impossible to bend or break.
CAUTION: Using a jack knife without a locking
blade is a good way to lose a finger.
4. A heavy duty, blunt screwdriver is commonly
used for shallow targets where digging or
“plugging” is objectionable.
and around the hole.
8. Recheck the hole and the area around the hole
with your 1280-X if you still can’t find it.
9. Once you have recovered the target, check
the area again. Two or more coins are often found
in the same spot.
10. Scrape all loose dirt back in the hole, reinsert
the plug and press it firmly in place with your foot.
TARGET RECOVERY

16
OPERATING TIPS
1. Keep the search coil cable wound snugly
around the stem when diving around coral or
jagged rocks to keep it from snagging.
2. Divers should make sure the drain holes in the
headset are unobstructed. Better yet, wait until
you’re on the bottom before putting them on and
take them off before surfacing.
3. Divers should also keep the search coil at least
two feet away from their body. Metal gear
(weights, gauges, tanks, etc.) will be detected by
the 1280-X if held too close.
4. Practice pinpointing. There’s nothing sacred
about the method described in this manual. Many
1280-X users have developed their own
pinpointing methods.
5. False signals may be caused by rapidly moving
surf, highly mineralized or trashy ground, large or
irregular shaped trash and bumping or raising the
search coil very fast. A false signal will generally
sound suspicious to the experienced treasure
hunter. It may be very faint, or very sharp and
abrupt with static. Often when you go back over
the same spot a false signal will simply disappear.
You may reduce the number of false signals you
get by increasing the discrimination level and/or
reducing the sensitivity level.
6. If you’re wading or hunting on land, hold your
digging tool behind your back or above your waist.
Your 1280-X is sensitive enough to sound off each
time you sweep your coil beneath it.
7. There is some sensitivity loss at the higher levels
of trash rejection. The greater the ground
mineralization, the higher the sensitivity loss. For
example, you may be able to detect a penny 6
inches deep at zero discrimination, but you may
be able to detect it no deeper than 5 inches at the
pull tab discrimination point.
8. Some objects such as shallow bottle caps, bent
pull tabs or trash less than 2 inches from the coil

17
may be difficult to reject. The 1280-X will instead
respond with a strong broken signal which will
usually disappear if the coil is speeded up or raised
slightly.
9. If you hear two beeps very close together and
can’t find anything under either one, you’re
probably over a nail or some other elonggated
ferrous object. But a coin on edge will give the
same response and there’s lots of coins on edge
down there. In either case, the target will be
between the beeps or, if you sweep at right angles
to your original direction, you’ll receive a single
beep directly over the target.
10. You may hear some static at a sensitivity level
of 10. This is normal, how ever if it is too loud or
annoying, reduce the sensitivity level to about 8 or
9, just enough to eliminate most of the static.
11. When in doubt about the probable identity, dig
it up.
OPERATING TIPS

18
BATTERY RECHARGING
Rechargeable nicad batteries may take as many as 1,000
recharges, however they do have some limitations you should
be aware of:1. Nicads will last only about half as long as
standard carbon-zinc batteries before
recharging is required.
2. Nicads may develop a “memory” if you give
them repeated “booster” charges. In other
words, if you charge your batteries over and
over again for only three hours at a time, the
Eight 1.5V size AA batteries are located in the rear section of
the Control Housing. The batteries are sealed off from the
electronics so that accidental water leakage into the battery
compartment will not damage the circuitry.
1. Remove the battery cover by partially
unscrewing the two knurled thumb screws with a
coin. (The knurled knobs are “captive screws” and
do not have to be completely removed from the
battery cover.)
2. Remove the battery pack from the Control
Housing and disconnect the battery lead
connector. Be very careful not to put any undue
strain on the battery leads.
3. Remove the batteries from the battery packs.
Note the polarity markings inside the pack and
install fresh batteries.
4. Reconnect the battery lead.
5. Insert the battery pack into the Control Housing
with the lead connector up, on the right side. Fold
the leads across the top of the pack.
6. Make sure the O-Ring and both sealing surfaces
are clean before reinstalling the battery cover. THIS
IS EXTREMELY IMPORTANT.
7. Finger tighten the thumb screws, then carefully
tighten again one-quarter turn with a coin.
BATTERY REPLACEMENT