Manual

Comprehensive Operating Manual & Guide to Metal Detecting
Comprehensive Operating Manual & Guide to Metal Detecting
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25
F75
F75
NOTCH
Unlike Discrimination Level, which eliminates all targets from the left of the scale to the right,
NOTCH can eliminate and re-include targets within the scale displayed at the top of the
display. Inclusion or exclusion of target ranges is indicated with a half-crossed or crossed icon.
To demonstrate how to set a notch, follow this instruction at first use.
1. Reset all detector values to default:
a. turn detector off
b. press-and-hold red MENU button and push-forward-and-hold Toggle Switch
c. turn detector on while continuing to hold MENU and Toggle
d. release Menu and Toggle.
2. Press MENU button 4 times to move down to the NOTCH feature
-then rotate the SETTINGS knob to the right until the number
40 appears.
-then press MENU again to accept this notch value.
3. Notice that a thin line appears across the word “TAB” printed on the top of the display.
4. Press MENU again to exit the NOTCH feature.
5. Targets in the first 1/2 of the TAB range (TAB range is from 36 to 55) will be eliminated
from detection.
6. A half-slash will be permanently displayed across the top-left of the word “TAB.”
NOTCH allows you to select target ranges equal to
1/2 of each category for inclusion or
exclusion from detection. As you rotate the knob, the target indicator will appear above the
range currently selected. If you set the notch value anywhere within the range, the notch value
will not necessarily stop at this number, notch ranges are fixed as follows:
1. 1-7 iron 6. 31-35 nickel
2. 8-15 iron 7. 36-45 tab
3. 16-20 foil 8. 46-55 tab
4. 21-25 foil 9. 56-60 zinc
5. 26-30 nickel 10. 61-65 zinc
The following are characteristics of NOTCH programming:
• As you rotate the knob to enter a notch range, the target indicator block at the top
edge of the screen illuminates to show you the range you are in.
• After you have selected a notch, a slash is illuminated over that range, indicating that
all targets within that range (see chart above)
are eliminated from detection.
• When you enter the program to make a
change to the notch settings, you are
changing the status of the notch. If no
slash is illuminated and you press MENU to
set a notch range, you will be notching-out this
range. If a slash was previously illuminated
and you press MENU to set this notch range,
you will be notching-in this range.
• Programming a notch range always
reverses the status of the notch.
Discrimination Mode (continued) LCD Visual Display (continued)
Since different metal objects can produce similar signals, and since minerals in the soil can
distort the signals, the probable target ID's are just that -- probable. There is no way of
knowing for sure what's buried other than to dig it up. Experienced metal detector users have
a rule of thumb -- "when in doubt, dig".
DEPTH
When the trigger is pulled to facilitate pinpointing an object, the 2-digit numerical display
indicates the approximate depth of the object, in inches, based on the assumption that the
object is a typical U.S. coin. Small objects will read deeper than they actually are, and large
objects will usually read shallower than they actually are.
The
DEPTH bar graph on the left of the display divides target depth into shallow, medium, and
deep. This depth range appears while searching, and is less accurate than the value derived
using the pinpoint toggle switch.
Bar graph ranges for a coin-sized object are Shallow (0-4inches), Medium (4-8inches), and
Deep (8inches +).
CONF (Target Confidence Indicator)
This 6-segment graphic indicates how confident the detector is of the 2-digit target
identification it has assigned. If all 6 segments are displayed, you can be confident that the
target ID is accurate. If 3 or fewer segments are displayed, the confidence is very low.
Junk targets tend to produce lower confidence indications than coin targets of similar electrical
conductivity. Sloppy sweep technique also reduces the confidence indication. You can use
this indicator to train yourself to sweep more skillfully.
Fe
3
O
4
BAR GRAPH (magnetite)
This bar graph displays the magnetic mineralization factor, or magnetic susceptibility, of the soil.
Magnetic susceptibility is expressed in terms of the percent volume of the iron mineral magnetite,
which most black sand is made of. The depth to which objects can be accurately identified is
strongly influenced by the magnetic susceptibility of the soil. High Fe
3
O
4
values have a greater
effect on detection depth in the Discrimination mode than in the All Metal mode. For the most
accurate Fe
3
O
4
reading, pump the searchcoil as though you were ground balancing.
Fe
3
O
4
approx.
Range micro-cgs Description
3 7,500 uncommon but not rare, heavy mineralization
1 2,500 heavy mineralization, not uncommon in goldfields
0.3 750 heavy mineralization, but not uncommon in some regions
0.1 250 medium mineralization, typical
0.03 75 light mineralization, but common
0.01 25 light mineralization, your G. B setting may also be low
blank <14 quartz & coral white beach sands
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