22
DUAL CONTROL, SAT
When in the Prospecting MODE the DUAL CON-
TROL is used to adjust the level or speed of SAT
(Self Adjusting Threshold). The Threshold or
continuous faint hum heard during operation of the
MXT can rise or disappear due to environmental
interference or by interference of ground mineral-
ization. This can be heard as chatter when exces-
sive. Faster SAT speeds tend to calm this interfer-
ence allowing for target sounds to be separated
from ground noise.
The MXT is computerized, which allows improved
SAT in ways not practical in the past. These im-
provements "kick in" progressively at higher set-
tings allowing better ground silencing in highly
variable ground. At these higher settings, cold
rocks (rocks well below the current ground mineral
rejection level) will sound "different" giving a
"double blip" sound or vanishing entirely, rather
than giving the "boing" sound you will get at lower
settings.
Another difference between a gold nugget and a
cold rock is that when you sweep back and forth ,
the gold nugget will "stay in one spot" but the cold
rock will seem to keep wandering around. This can
also be the case with a pocket of negative mineral-
ization.
GAIN and VARIABLE SAT (Self Adjusting
Threshold) Speed:
The TRAC feature compensates for common
ground minerals in the area. The SAT control
compensates for the inconsistency of the ground
mineralization. The greater the degree of inconsis-
tencies, the more SAT is needed to quiet ground
noise. If the THRESHOLD becomes too erratic or
noisy, it might be necessary to use the SAT feature
and/or reduce the GAIN control. This noisy behav-
ior will make it difficult to recognize a true target
(possible nugget) from pieces of mineral, com-
monly referred to as "hot rocks". It is not wise to
keep a high level of GAIN if the detector will
not operate smoothly. This is a false sense of
security. Maintain as smooth a threshold as you
can.
Recognizing a true target is the most important part
of detecting. This is an example of when less
GAIN will produce more nuggets. You must be the
best judge of just how much noise you can tolerate
and still identify nuggets, and thus the amount of
SAT and GAIN to use to produce the desired results
in your area. Therefore, if you have been operating
your MXT at the full level of GAIN (+3) and you
determine that this is too high because either the
threshold is erratic or the detector is giving false
signals; always begin by reducing the GAIN toward
the Initial Setting triangle. If this does not correct
the problem, start adding some SAT speed by
turning the SAT control slowly clockwise. If this
does not correct the problem, go back to the GAIN
and reduce it a little more and add a bit of SAT. As
I mentioned earlier it is sort of like seasoning a pot
of soup. Some salt and some pepper. Remember
any drop in GAIN below (7-8) will result in some
loss of depth. Any increase in SAT speed above the
"P" setting may also effect overall depth.
However, before reducing the Gain below 7 - 8 you
might try to experiment a bit with the HYPERSAT
range of the SAT control. This function is unique
to White's SAT. The Threshold will almost buzz
and loss of depth will be minimal. Reserve this
option for situations where ground is unusual or
conditions extreme. If you can't control your
Threshold with small reductions in Gain or small
increasing SAT, then "jump start" your SAT into
the HYPERSAT range. Before attempting this, you
might practice sweeping over a test nugget to learn
to identify it's sound with HYPERSAT.
We like to use the analogy of driving on a straight
road versus a curvy road. The object is to get from
point A to point B. 65 m.p.h. might get you there on
a straight road, but you will have to slow to 35
m.p.h. if the road is curvy, or you will end up off
the road. The straight road is like low mineralized
ground and the curvy road is like heavy mineraliza-
tion. High Gain and slower SAT will not get you
the Gold in heavy mineralization as well as lower
GAIN and faster SAT.
Chapter 5 MXT Controls
Chapter 5 MXT Controls
