Interpreting The Display And Acoustic Signals; False Signals; Factors That Affect Detection Accuracy - Renkforce MD 100 Notice D'emploi

f) Interpreting the display and acoustic signals
Switch on the metal detector. You may hear a beep after it is switched on. The display/audible signal that indicates a
metal object depends on a number of factors as well as the metal detector settings.
• The amount by which the pointer on the analogue display (12) moves indicates the distance of the detected signal
(normally the metal object). The volume of the audible signal increases as the detection probe (1) gets closer to the
signal source and decreases as the detection probe moves away.
• When the DISC dial (15) is set to the minimum position, the metal detector eliminates ferrous metals. Moving the
DISC (15) to the right allows you to distinguish between aluminium and nickel (depending on the setting). Silver
cannot be distinguished from other metals, even at the highest discrimination setting.
• When the metal detector detects an eliminated metal, the pointer moves anticlockwise to the left-hand side of the
display (12). The metal detector does not give an audible signal (or the audible signal is very weak).
• When the metal detector detects another non-ferrous metal or alloy, the pointer moves clockwise to the right-hand
side of the display (12), and the metal detector plays an audible signal, the volume of which indicates the distance
and size of the detected object.
g) False signals
• A false signal occurs when the metal detector incorrectly indicates that there is a metal object. Move the detection
probe (1) over the position of the signal several times. If the signal is strong and consistent, this indicates that the
metal detector has detected an object under the ground. If the signal is irregular or inconsistent, this is likely to
indicate a false signal. Identifying false signals requires practice and experience. False signals can occur for the
following reasons:
• The sensitivity is too high.
• The metal detector was moved too quickly or at an incorrect angle.
• There are several different metal objects.
• The object consists of an alloy that the metal detector cannot recognize.
• The metal object is heavily oxidized. There is a "halo" effect.
h) Factors that affect detection accuracy
• The success/accuracy of the metal detector depends on several factors. These include:
- The angle at which the object is inserted in the ground (detection area)
- The depth of the object
- The object's degree of oxidation
- The size of the object
- Electromagnetic and electrical interference (e.g. underground cables) in the vicinity of the object
• Due to these factors, it is important that you familiarize yourself with the metal detector and how it responds before
attempting to search for objects. See "e) Testing reactions to different types of metals" for details. Learning to detect
false signals requires practice.
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