13
Comprehensive Operating Manual & Guide to Metal Detecting
PRO-TECH
24
PRO-TECH
Comprehensive Operating Manual & Guide to Metal Detecting
GROUND BALANCING (continued)
The goal of the Ground Balancing procedure is to eliminate the sound as the
searchcoil is being pumped over the ground. In some soils, the sound is not
completely eliminated.
After balancing to ground with GG some users may want to further adjust the ground
balance point manually.
To manually adjust ground balance:
1. Operate in ALL METAL Mode.
2. Pump searchcoil up and down over the ground as in the GG procedure.
3. Press
+
or
-
while pumping
If the Ground Balance adjustment is incorrect, there will be a difference in the sound
as the searchcoil is either moving toward or away from the ground. It sounds like
you are either
pulling the sound out of the ground,
or
pushing the sound into
the ground.
• If the sound is louder as you raise the searchcoil, increase the ground
balance setting.
• If the sound is louder as you lower the searchcoil, reduce the ground balance
setting.
NOTE: Experienced users often prefer to adjust the ground balance to get a weak
but audible response when lowering the searchcoil. This is called
adjusting for
positive response.
Positive and Negative Response
The purpose of Ground Balancing is to adjust the metal detector to ignore ground
minerals. If the setting is incorrect, ground minerals will give either a
positive
or a
negative response, depending on which direction the adjustment is off.
Positive Response
If the GND BAL setting is too high a number, the response of minerals will be
positive
. This means that when the searchcoil is lowered to the ground in PinPoint
or All Metal Mode, the sound will get louder as the searchcoil approaches the
ground. The sound will grow quieter as the searchcoil is raised. What, if anything,
you will hear in Discrimination Mode depends on the discrimination setting.
When searching in an All Metal Mode, if ground balance is properly set to cancel the
ground, and you sweep over a
positive hot rock,
the rock will give a “zip” sound
similar to that of a metal object.
Negative Response
If the GND BAL setting is too low a number, the response of minerals will be
negative
. When the searchcoil is lowered to the ground in PinPoint or All Metal
Mode, the machine will be silent. The machine will sound off as the searchcoil is
lifted away from the ground. What, if anything, you hear in Discrimination Mode
depends on the Discrimination setting.
When searching in All Metal Mode a
negative hot rock
will produce a “boing” sound
after passing over it, making it difficult to know where it is located. It will not have the
sound and “feel” of a metal object.
OPERATION & CONTROLS
POWERING UP
NOTE:
Immediately after powering on, your detector's unique 10-digit serial
number is displayed once on the LCD. Two digits are displayed at a time; five 2-
digit numbers are displayed in sequence. This 10-digit serial number is the same
serial number imprinted on the label inside the battery compartment.
Click the left knob to turn the detector ON.
After clicking the knob on, continued clockwise rotation will increase the
“sensitivity” in DISC Mode or the “GAIN” in ALL METAL Mode.
We suggest keeping the GAIN below 70 until you become familiar with the
detector's operation.
• In DISC Mode press-
and-hold to enter
no-motion
PINPOINT Mode
• In ALL METAL Mode
press-and-hold
while bobbing coil,
to set ground
balance
In DISC Mode:
Change discrimination level from 0 to 80
In ALL METAL Mode:
Change Ground Balance
setting from 0 to 99.9
HOW TO WORK
THE CONTROLS
ON/OFF/GAIN:
• Click ON/OFF
• In DISC Mode rotate
to change GAIN
(sensitivity) from
1 to 100
• In ALL METAL Mode
rotate to change
GAIN from 5 to 100
in steps of 5
MODE SELECTION
and THRESHOLD CONTROL
• Click left to operate
in DISCrimination
Mode
• Click to right to
operate in ALL METAL
Mode.
• Rotate knob in
ALL METAL Mode to
change THRESHOLD from
-40 to 40
ProTechMANUAL_MPROTECH 1/28/15 8:14 AM Page 26
