Backlight & Battery Life - White's GOLDMASTER Series Owner's Manual

GMX SPORT Searching
Another option is to run the GMX in XGB mode, and after hearing a faint target signal,
immediately locking the ground balance. Now you can double check the target from
different angles without the XGB "tracking out" that target. This provides the best of both
worlds - automatic tracking but the option to freeze it after acquiring a signal.
If hot rocks are driving you crazy, you can also ground balance directly over the hot rock,
then lock the tracking. If the rest of the ground matrix does not give you a false signal
after doing this, you have successfully cancelled not only the ground but also hot rocks!
Backlight and Battery Life
With a short tap of the power button, the GMX's backlight will turn on, giving increased
visibility in low light conditions. In bright sunlight it will not be obvious this backlight is en-
abled, so there is a light bulb icon to indicate the status as well (icon on = light on). This
light consumes a great deal of power so it is best used only when necessary, as it may
lower the operating time by 50%.This backlight is on for a few seconds when powering
on the GMX, but only to allow for those situations when the unit is turned on in total
darkness. It will turn itself off after a few seconds and the icon will disappear until the
backlight is enabled or the detector is powered back on again.
Operating the GMX in Extreme Mineralization: Thanks to the combination of XGB
ground balance, SAT, and Iron Cancel, the GMX is able to operate in a wider variety
of conditions than many other VLF detectors. However, it takes some knowledge of
how to use each setting to combat bad ground, and the differences between types
of ground. In very strong mineralization, such as heavy iron stone or serpentine, it will
be necessary to lower the sensitivity. There is enough voltage at the search coil to
cause the GMX to overload in bad ground, so take some time to find a good setting
for sensitivity before making other adjustments. To check the ground strength you
can enable Ground Scan by holding the LOCK button. Another issue you may run into
is highly variable ground mineralization. In these conditions you will not get an overload
response, but will have to contend with lots of false signals with your coil sweep. This
is a result of the ground phase shifting rapidly under the coil. The first step you should
take is to increase your SAT setting by holding the Music Note button, and then tapping
the Up button to set the SAT to a higher setting. This will allow the detector to adjust
more quickly to the rapid ground changes. As a last resort, enable the Iron Cancel fea-
ture (the crossed-out nail button). This will not allow those low-range signals to break
through the threshold in either audio mode. Only in the most extreme conditions should
you adjust the Iron Cancel (by holding the crossed-out nail button) to higher settings.
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