Garrett Metal Detectors Metal Detectors GTAx 550 - Manual (Page 48)

Since the 550 is a motion detector, it is capable of
finding only somewhat larger nuggets (at least BB
size).
It must be emphasized that prospectors using the
GTAx 550, or any other quality detector, usually
prefer to operate in the Zero Discrimination Mode.
When prospecting, discrimination may reduce the
amount of small nuggets found, but some areas
contain so much iron trash that a small amount
of discrimination becomes highly desirable, even
necessary. A special notch can eliminate a particular
junk metal target if needed.
Hard work, patience and research are three of the
keys to success in electronic prospecting. Research
is important because it is vital that gold always be
found in areas where it is known to exist. More
information is contained in You Can Find Gold with
a Metal Detector.
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