18
Chapter 5 MXT Controls
Gain Control/ON-OFF
With the GAIN control, you turn the instrument on/
off and select the signal strength. You might expect
increased signal strength to always find more at
greater depths. However, high ground mineraliza-
tion will "bounce" the signal back and mask good
targets. It is therefore necessary to ADJUST the
GAIN to give you the maximum allowable GAIN
without masking targets or overloading the circuit
and at the same time allowing you to operate the
detector with a constant faint threshold hum so that
faint signals (deep or small targets) can be detected.
This is where the new MXT can help you out.
When ground mineralization is too high for the
current GAIN control setting, the display indicates
"OVERLOAD-REDUCE GAIN/LIFT LOOP"
along with an audible "squawk". Reduce the GAIN
till the overload warning ceases. On occasion,
while searching, you might sweep the loop over a
very large or very shallow target. The message on
the LCD display will read "OVERLOAD-RE-
DUCE GAIN/LIFT LOOP". All such targets
should be checked by sweeping the loop a little
higher over the area and noting the display and
audio indications. The MXT will self correct after
the message and you can continue to search as
normal.
Gain Adjustment
1. The GAIN control knob turns the MXT ON and
OFF and controls the GAIN. Starting from the
POWER OFF position and going clockwise, the
power is turned ON and the dial increases the
GAIN from a minimum level of "1" to a maximum
level of "+3". Set the control to the "Initial Setting
Triangle" ( between level 9 & 10 ).
2. Although the setting of (9-10) gives more than
ample GAIN, if the ground mineralization is low
enough, you might attempt to raise the GAIN above
this level 3.
GAIN Control
NOTE: Ground Mineralization too high, large or shallow target
message.
Chapter 5 MXT Controls
