Kellyco Titan 9000, Руководство пользователя

Страница: 25 / 38

▲
False signals and chatter; using the Sensitivity control
At times the machine may "beep" when there's nothing there, or at
least it seems like there's nothing there. There are three main
causes of this: electrical interference, nuisance buried metal objects,
and electrically conductive ground minerals. Usually, reducing the
sensitivity by tapping the Sensitivity Low (minus) button will help,
but sometimes other corrective measures will also be needed.
ELECTRICAL INTERFERENCE can be caused by powerlines,
appliances, fluorescent and vapor type lamps, light dimmers, other
nearby metal detectors, electric fences, radio transmitters and
electrical storms. If you get noise even while holding the loop
motionless in the air, the cause is electrical interference. By
walking around with the metal detector, you can often "follow the
signal" and track it back to the offending device, and simply turn
the offending device off. If it's from a powerline or a
communications transmitting antenna, reducing sensitivity is
usually a satisfactory solution to the problem. Switching to another
searchcoil, even of the same size, often helps, and switching to the
smaller 4 inch searchcoil usually helps.
NUISANCE BURIED OBJECTS In some areas there is a lot of
metallic trash which produces weak signals, including items buried
deeply, and little bits and pieces of rusty iron and corroded foil
which are shallow. These items can be detected, but they are often
difficult to find because of their depth or small size. It may seem
like the machine is beeping at nothing. The best solutions are to
reduce sensitivity, and to discriminate out iron and foil. Using the 4
inch coil can also help by reducing sensitivity to deep targets and by
giving a crisper "feel" on shallow targets.
Metal detectors are designed to "see" one metal object at a time. If
pieces of iron are laying next to each other, such as can happen on
sites where a building has burned or been torn down leaving lots of
nails in the soil, this can confuse the machine into thinking there
are nonferrous targets present. This can cause high tones to occur
even though there is only iron metal present. The way you can tell
the difference , is that a nonferrous target will usually beep
consistently and in the same location, whereas false high tones
caused by too much iron trash are inconstant and seem to wander
around-- what experienced detectorists call a "nonrepeatable signal".
The 4 inch coil provides better signal separation and so exhibits
fewer false signals and better identification of good targets when
searching under trashy conditions.
GROUND MINERALS In irrigated soils and in the wet areas of salt
water beaches, electrically conductive salts can cause the ground
signals to fall outside the range which can be ground balanced. This
usually causes false low tones. The problem can usually be solved
by reducing sensitivity and/or by discriminating out iron and foil.
25