Page 12
Coinmaster GT
Owner’s Manual
Overload
If the received signal is too large to process the
CoinGT
will
give an
overload
response. This is heard as an obnoxious alarm
sound, plus the display will read “OL”. An overload can be the
result of a large metal target near the surface, or from extreme
ground mineralization. If it is the latter, the only recourse is to
reduce the sensitivity level until the detector can operate
smoothly.
Coil Size
With any metal detector, the size of the search coil presents
a trade-off between depth and sensitivity. A larger coil offers
better depth on larger targets at the expense of small-target sen-
sitivity, and a smaller coil has better sensitivity to small targets,
but at a lesser depth. Small coils also do a better job of separat-
ing targets when hunting in trashy areas.
The
CoinGT
comes standard with a 9” concentric coil. An
optional 4x6 “DD” coil is also available.
Sweep Methods
Proper sweep technique is
important with any detector.
Round coils tend to have a
conical pattern of sensitivity
as illustrated here. As such,
coverage at maximum depth
is less than the size of the coil,
so it is always recommended
that successive sweeps are
overlapped by about 50%.
Besides overlapping each sweep, it is important to keep the
coil close and parallel to the ground. Pendulum-swinging the
coil results in loss of depth, and if the ground balance isn’t per-
fectly set the variation in loop height will create a ground
response. The following illustration shows improper and proper
coil sweep motion.
