One of the following may happen as a result of improper ground balancing:
-The device gives a signal when the coil is swept over the ground where there is no target.
-The device is silent but loses detection depth for certain metals.
-The device receives target-like signals next to holes and dips.
The above mentioned situations do not only occur as a result of improper ground balance
adjustment. However, before looking into other reasons you must be sure that the ground
balance is correctly adjusted.
Ground balance value is common to all modes; changes will take effect in all modes. When
using the automatic ground balance or ground tracking, this setting is adjusted
automatically.
Ground balance can be done in three ways in FORS CoRe: Automatic, Manual or Ground
Tracking.
During automatic or manual ground balancing, when you press the ground balance
button, no matter what mode you are using, the device will unnoticeably revert to the
General Search mode and the audible tones will be heard accordingly.
AUTOMATIC GROUND BALANCE:
Automatic ground balance is done the same way in all modes:
1. Find a spot on the ground where there is no metal.
2. Press and hold the ground balance button and pump the search coil up and down from
about 15-20 cm (~6''- 8'') above the ground down to 3 cm (~1'') off the ground.
3. Continue until you hear the beep indicating that the ground balancing is completed.
Based on ground conditions, it usually takes about 1-4 pumps for the ground balance to be
completed.
4. Once the ground balance is done, the ground balance value will appear on the LCD
panel as well as the numeric display on the handle. If you continue to press and hold the
ground balance button, the device will keep on ground balancing and beeping. To make
sure that the ground balance adjustment is correct, please repeat the process 2 or 3 times
and each time check the value on the display. The difference between the values should
not be greater than 1 or 2 numbers.
5. If you cannot ground balance, meaning you don't hear the beep, either the ground is
very conductive or not mineralized or there must be a buried metal object underneath the
coil. In such a case, move to another location and re-ground balance. If you still cannot
succeed, try manual ground balancing.
After the ground balance button is released, the device will work in the General Search
mode and the ground balance value will remain on screen for a while. (If you do not want
to wait for this period you can go to the main screen by pressing and releasing the pinpoint
button once). This gives you the opportunity of fine tuning the automatic ground balance
value. Please refer to the following MANUAL GROUND BALANCE section for more details.
MANUAL GROUND BALANCE:
It is the process where you set the ground balance value manually. Because it is more time
consuming, it is not preferred by most users. However, it becomes useful when ground
balance cannot be achieved by other methods or when you need to fine tune the
automatic ground balance value.
FORS CoRe is designed in a way that you can easily auto ground balance it on all types of
ground. Therefore, we recommend that you use automatic ground balance at start up.
However, some soils are not suitable for automatic ground balancing (except for the COG
mode). For example; wet beach sand, soils containing alkali or salty water, trashy areas,
plowed lands, highly mineralized ground or ground with very low mineralization are not
suitable for automatic ground balancing. We recommend you to manually ground balance
in such areas for your convenience. Manual ground balance requires experience acquired
with some practice.
To ground balance manually:
1. Find a spot on the ground where there is no metal.
2. Pump the search coil up and down from about 15-20 cm (~6''- 8'') above the ground
down to 3 cm (~1'') off the ground.
If the sound gets louder as you lift the search coil off the ground, it means that the ground
balance value is too low. In other words, the ground is negative and you need to increase
the ground balance setting with the up switch. On the contrary, if the sound gets louder as
you lower the search coil to the ground, it means that the ground balance value is too high.
In other words, the ground is positive and you need to lower the ground balance setting
with the down switch.
3. Press and release the ground balance button once. The ground balance value will appear
on the LCD panel and will stay on screen for a while. If the screen changes, you can press
the ground balance button again.
To increase the ground balance setting, press the up switch and to decrease it, press the
down switch. If you press the switch one by one, the values will change one by one as well.
If you hold the switch pressed, the values will change rapidly.
Manual ground balance ranges from 0-99. However each
number includes 5 steps used for fine tuning and these
steps are shown on the LCD panel over the symbol
and in multiples of 20. For example; the ground balance
value on the screen to the side is 60.20.
Ground
Balance
Pump The Coil
20
60
Ground
Balance
Pump The Coil
20
60
FORS / Page 18
www.noktadetectors.com
NOKTA DETECTORS
GROUND BALANCE
