Noise Cancel - Minelab E-Trac Instruction Manual

a Simple Detecting exercise
30
Detector Sounds
(cont)
The Target Response is the sound produced
by the detector when a target is detected
and not 'rejected' . A highly conductive target
(e.g. a large silver coin) will generally produce
a high-pitched tone and a low conductive
target (e.g. foil) will generally produce a low-
pitched tone. Large targets or targets close to
the ground surface emit louder signals (p. 57).
When a 'rejected' target is detected, the
Threshold 'blanks' (becomes silent), indicating
that a target is located underneath the coil,
but has been rejected by the Discrimination
Pattern (p. 20). Blanking is a useful way
of distinguishing between desired and
undesired targets.
Note: As the coil passes over the nail, the
Threshold 'hum' momentarily
disappears (blanks).
Target Response
Threshold
'Blanking' (No Sound)
Threshold
Large objects close to the coil may Overload
the detectors electronics. When this happens,
E-Trac displays an Overload message and
emits a fading Overload sound which repeats
until the coil is moved away from the source
of the overload.
Overloading is not harmful to the electronics
of the detector.
It is important to understand the sounds
produced when you make a valid or invalid
button press. You will usually encounter these
sounds while adjusting settings via the Main
Menu. A valid button press makes a "bip"
sound, an invalid button press makes a
"ba-dump" sound.

noise Cancel

The E-Trac may become noisy due to
electrical interference from power lines,
electrical equipment or other detectors
operating close by. The detector interprets
this interference as inconsistent, short beeps
and erratic movement of the Target Crosshair
in the Smartfind window, or erratic changing
of FE-CO numbers in the Digital display.
Noise Cancel is used to minimise interference
in the current environment. The channel can
be changed automatically by pressing the
Noise Cancel button or manually in the Noise
Cancel setting via the Expert Menu (p. 75).
Automatic Noise Cancel
The Noise Cancel button instructs the
detector to automatically listen to every
channel and select the channel with the
least interference. Automatic Noise Cancel
may take up to 30 seconds. The detector
will display the progress on the LCD display
and a tune will sound at the end of this
period. After the Noise Cancel is complete
the chosen channel will be displayed
momentarily and then the detector will
resume normal operation.
To initiate an Automatic Noise Cancel:
1 Hold the detector 30cm (12") above the
ground and make sure there are no large
targets or obvious sources of EMI close by.
30cm
(12")
2 Press the Noise Cancel button. Keep
the detector 30cm (12") above the
ground and completely still during the
automatic channel selection.
Note: This may take up to 30 seconds.
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