17
Comprehensive Operating Manual & Guide to Metal Detecting
PRO-TECH
OPERATING IN ALL METAL MODE (continued)
Reading the Display
As you sweep the searchcoil, notice the Fe
3
O
4
(iron oxide) scale to the left of the
display.
This indicates the amount of ground mineralization.
For the best depth detection in highly mineralized soils, use the All Metal Mode.
For the most accurate Fe
3
O
4
reading, pump the searchcoil over the ground.
While sweeping the searchcoil, also notice the GND PHASE value in the middle of
the screen.
GND PHASE is the ground phase; this indicates the type of minerals in the soil.
Within an area, the ground phase may change.
After ground balancing, periodically compare GND PHASE to GND BAL. If these
two numbers differ by a great deal, you may want to ground balance the
detector again.
When not adjusting the knobs, the GND BAL setting will always appear on the
bottom-right of the display.
GND BAL is the detector's internal ground balance setting. The detector's default
ground balance setting is 82.9, which is the best starting point for achieving the
correct setting.
After you perform the Ground Grab
®
procedure, the GND BAL number will
change to match your soil.
You can change the current GND BAL setting by pressing the + or - buttons.
See section on Ground Balancing for a more detailed explanation.
Experienced users often prefer to adjust the ground balance to get a weak
audible response when lowering the searchcoil to the ground. This is called
adjusting for positive response and is achieved by increasing the GND BAL
number with the + key.
Target Scale
The arc across the top classifies metal objects.
Each time a target is detected, three segments will illuminate above the arc.
The segments will remain illuminated for three seconds.
This indication shows the approximate classification of the buried metal object.
See the section on Target Display for a more detailed explanation.
Iron is on the left. Silver and copper metals are to the far right.
In an air test, gold indicates right of center -- the larger the gold piece, the
farther to the right.
If searching in All Metal Mode, you may want to switch back into
Discrimination Mode, after finding a target, to see a more accurate target
identification, viewing the 2-digit Target.
20
PRO-TECH
Comprehensive Operating Manual & Guide to Metal Detecting
OPERATING IN DISCRIMINATION MODE (continued)
Or it may be a coin-sized metal object close to the surface.
If only a few bars illuminate, the target signal is weak.
This may be a deeply buried object, even a big one.
Or it may be a very, very small metal object, close to the surface.
The depth of a coin-sized object can be confirmed using Pinpoint.
In Discrimination Mode, pr or - will change two detection parameters:
1. Tone Identification
2. Target Elimination
As the level of discrimination changes, the target segments along the arc on the
screen will be displayed in one of three states:
1. Blank (no segments displayed)
2. Grey (segments displayed in a shaded color)
3. Black (segments are solid black)
The segments along the arc will remain illuminated in this state as you are pressing
+ or -.
This displays your chosen target discrimination parameters.
At any time during operation, you can view the discrimination settings in one of two
ways:
1. On the bottom-right of the screen the DISC value is always illuminated.
a. This value is the division between the LOW tones and V.C.O. tones.
b. This value is the lowest target value which will be detected with a
V.C.O. tone.
2. Whenever you press + or -, the arc will illuminate and show your current
detection parameters.
The first press of + or - will change the discriminate level by one value.
When a target is detected, the rectangular segments representing the target category
are illuminated.
Discrimination Control continued on next page
