GROUND BALANCE
Metal detectors work on the principle of conductivity and all metals are conductive. On the
other hand, soil itself has a certain degree of conductive property. Under certain
conditions, the conductivity level of the soil may be very high. Soil and rocks have
magnetic properties as well as conductivity. For this reason, when searching in soil and
between rocks, in order for the detector not to give a target signal for the soil, the detector
should be able to eliminate the soil and minimize the effects of rocks while still detecting
real targets. Otherwise, false signals and noise may mislead the user and make it
impossible to find the target. The purpose of ground balancing is to eliminate these false
signals and noise.
When you sweep the search coil over the ground, you can see whether the ground balance
is adjusted properly or not. However, if the signals and noise continue when the coil is
raised up, you must consider the possibility of the electromagnetic waves in the
surrounding environment. Electromagnetic waves may result from power lines or from the
operation of electrical devices, radars, wireless radios, and even TVs. In such a case, first
make sure that the device is silent by making the sensitivity and threshold adjustments
and then ground balance.
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 Relic: 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.
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