9
4. Size and Depth of Buried Objects
The relative depth of an object is displayed at the left of the display as a 1
digit number, 0 to 9 inches. The size of an object can be determined using
sweep techniques described later in the manual.
5. Electromagnetic Interference (EMI)
The search coil produces a magnetic field and then detects changes in that
magnetic field caused by the presence of metal objects. This magnetic field
that the detector creates is also susceptible to the electromagnetic energy
produced by other electronic devices. Power lines, microwave ovens,
lighting fixtures, TVs, computers, motors, etc…. all produce EMI which can
interfere with the detector and cause it to beep when no metal is present,
and sometimes to beep erratically.
The SENSITIVITY control lets you reduce the strength of this magnetic
field, and therefore lessen its susceptibility to EMI. You may want to operate
at maximum strength, but the presence of EMI may make this impossible,
so if you experience erratic behavior or “false” signals, reduce the
sensitivity.
THE BASICS
continued
OPERATION and CONTROLS
cont.
NOTCH
continued
For example, the following settings tell
us that:
• The nickel, dime, quarter, and
50¢+ categories will be
detected.
• All other categories of targets
(iron, foil, alum, and zinc) will
not be detected.
3. SENSITIVITY
Use and to
increase
or
decrease sensitivity while the SENS line is highlighted.
Maximum sensitivity is indicated by 5 bars.
Minimum sensitivity is indicated by 1 bar.
If the detector beeps erratically or beeps when there are no metal objects
being detected, reduce the sensitivity.
The search coil produces a magnetic field and then detects changes in that
magnetic field caused by the presence of metal objects. This magnetic field that the
detector creates is also susceptible to the electromagnetic energy produced by
other electronic devices. Power lines, microwave ovens, lighting fixtures, TVs,
computers, motors, etc…. all produce EMI which can interfere with the detector and
cause it to beep when no metal is present, and sometimes to beep erratically.
HOW DEEP WILL IT GO?
The Alpha Metal Detector will detect a coin-sized object, like a quarter, to a
distance of about 9” from the search coil. Large metal objects can be detected
to a depth of several feet. Detectability is directly related to the size of the metal
object -- the larger the object, the deeper it can be detected.
Accuracy of target identification is also related to distance from the coil.
Beyond a distance of 8”, the accuracy of target identification begins to
diminish.
4. VOLUME
While the VOLUME line is highlighted, use
and
to change the
speaker volume.
The default volume setting is 9. Maximum is 9.
Minimum is 0 (volume off). At levels 1, 2 and 3, high tones will be inaudible or
barely audible.
The speaker volume will diminish as battery voltage drops. For maximum
speaker volume, use 1 or 2 tones, as the low and bass tones generate the
loudest sounds.
menu
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