White’s Electronics TDI Pro - Manual (Page 22)

22 TDI Pro Owner’s Guide
Ground Balance. Ground Balancing is more diffi cult at higher GAIN set-
tings. If it appears impossible, reduce GAIN and try again.
If the Pulsescan TDI Pro does not require ground balancing, there is another
option. When pumping the search coil 1-6 inches over the ground and turning
the COARSE GEB control, if the COARSE position makes no difference, there
isn’t any change in the Threshold regardless of the COARSE control position,
the Pulsescan TDI Pro can be operated as a standard pulse detector with no
variable audio, by turning the FINE control fully counter clockwise to off. All
targets will now sound the same. The upside the detector may detect deeper in
such low mineral grounds. Downside is you dig everything.
If the Pulsescan TDI Pro does achieve ground balance (COARSE control
position DOES infl uence Threshold as the search coil is pumped 1-6
inches over the ground), the FINE control must be used Clockwise of OFF.
The Ground Balance, Variable Audio, and TARGET CONDUCTIVITY feature
will be active. This situation indicates that there is enough iron mineralization
to balance. Again, the FINE control must be in the ON position (clockwise
from OFF) when the COARSE GEB makes a difference in Threshold as the
search coil is pumped 1-6 inches over the ground, and you must select a
target conductivity option.
If you are not able to fi nd a ground balance point (Threshold remains steady,
COARSE makes no difference) there are two options –
Option #1
You may search with the GEB FINE control OFF (fully counter clockwise). This
eliminates the Ground Balance, Variable Audio Tone feature, and the selectable
target conductivity feature. The Pulsescan TDI Pro circuitry handles the ground
mineralization with its inherent Pulse Induction capabilities. All targets will sound
alike, however, greater detection depth may be noted when searching low
mineralized grounds.
Option #2
Turn GEB FINE control clockwise On. This activates the Ground Balance, Audio
Tone, and selectable TARGET CONDUCTIVITY feature.