The Basics Of Metal Detecting; Ground Minerals; Trash; Identifying Buried Objects - Fisher F11 Owner's Manual

MF11-manual_MF11-manual 5/28/15 10:46 AM Page 18

THE DISPLAY

Coin-sized objects will be detected up to
DEPTH INDIC TOR
8" deep.
The 6-segment graphic indicator is
calibrated to coin-sized objects.
Objects other than coins will still register
on the 6-segment depth scale, but the
depth indication will be relative. For
example, all 6 segments illuminated
could indicate a coin buried 8" deep, but
could also be a very large object several
feet deep. Use the Depth Indicator in
conjunction with the Target Category
Icons to gain more information.
If a metal object or highly magnetic soil are too close to the searchcoil, the
OVERLO D W RNING
detector will overload and begin emitting a rapid, repeating mid-tone warning
sound. Overload will not harm the detector, but the detector will not function
under these conditions. If overload occurs, raise the searchcoil to detect the
target from a greater distance, or move to a different location.

TARGET IDENTIFICATION

This is a motion detector. The searchcoil must be in motion to detect metal. A

Target-ID

motionless searchcoil over a metal object will not detect metal. When objects are
detected, the detector will emit a sound. A Target Category Icon will illuminate
indicating the Target-ID of the last object detected. This detector has fast target
response and is able to detect different objects in very close proximity. Therefore,
the Target-ID displayed may change rapidly as you sweep the searchcoil.
The Category Icon will remain illuminated for 3 seconds and then disappear.
Note: There are a wide variety of metals and no target can be identified for certain
until unearthed. See table on page 13 for a Target-ID Category coin reference.
The detector will provide 1 of 4
4-Tone Target Identification
sounds for any metal object
detected: bass, low, medium or
high tone. This audio feedback
system is useful in conjunction
with the visual Category Icon
system described above.
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Target Category Icons
Icons will turn from outlined to solid indicating a
detected target. A "blank" position indicates a
Notched-out target category.
Target Category
Iron
ID Numbers
Menu Target Mode
Category Depth Indicator
Icons Indicator
Battery Level
Indicator
Target Conductivity Bar
Silver
Iron Gold
Range Range Range

THE BASICS OF METAL DETECTING

This metal detector is intended for locating buried metal objects. When
searching for metals, underground or on the surface, you have the following
challenges and objectives:
1. Ignoring signals caused by ground minerals.
2. Ignoring signals caused by metal objects that you do not want to find,
like nails.
3. Identifying a buried metal object before you dig it up.
4. Estimating the size and depth of objects, to facilitate digging them up.
5. Eliminating the effects of electromagnetic interference from other
electronic devices.
Your metal detector is designed with these things in mind:
All soils contain minerals. Signals from ground minerals can interfere with

1. Ground Minerals

the signals from metal objects you want to find. All soils differ, and can
differ greatly in the type and amount of ground minerals present. This
detector has proprietary circuitry to automatically eliminate interfering
signals from minerals that occur naturally in the ground.
NOTE: This detector will not completely eliminate interference from all
types of minerals. For example, the detector IS NOT designed for use on
wet sand saltwater beaches. Another example of soil this detector will not
eliminate is any soil containing large concentrations of iron oxides, which
are usually red in color.
If searching for coins, you want to ignore items such as aluminum foil and

2. Trash

nails. You can see the Target-ID of the buried objects, listen to the sounds
and then decide what you want to dig up. Or, you can eliminate unwanted
metals from detection by using the NOTCH feature.
Metal objects are identified along the 9-segment Conductivity graphic

3. Identifying Buried Objects

symbols. This scale is an indicator of the relative electrical conductivity of
different objects. Segments to the right indicate more conductive targets. Iron
objects, which are usually of lesser value, illuminate on the left with the Fe
symbol. Silver objects will be illuminated on the rightmost segments.
The 6-segment graphic indicates the relative depth of a buried metal object.

4. Depth of Buried Objects

For a given object, the more distance between it and the searchcoil, the
more segment lines illuminated.
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