33
Comprehensive Operating Manual & Guide to Metal Detecting
PRO-ARC
22
PRO-ARC
Comprehensive Operating Manual & Guide to Metal Detecting
5
Fe
3
O
4
Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Battery Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Ground Balance (GB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Setting Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52-53
Backlight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
Frequency Shifting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54-55
Capabilities & Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..56-61
Tips & Techniques
Search Techniques
How to sweep the searchcoil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62-63
Boost and Cache Locating Processes . . . . . . . . . . . . . . . . . . . . . . . . . . .63-65
Pinpointing targets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65-66
Estimating target size and depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66-68
False signals and chatter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68-70
Ground minerals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70-71
Hot Rocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71-72
Adjusting Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
Tips on ground balancing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73-75
Shallow Water Hunting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Salt Water Hunting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
How metal detectors work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76-77
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Back Page
76
Search Techniques (continued)
SALT WATER HUNTING
Salt water is highly conductive, and produces a strong signal which is like that of metal. The
PRO-ARC is not specifically designed for high performance in salt water, but can be used in
this environment.
If you desire to search in or over salt water, the following measures will usually be sufficient to
silence the salt water response while retaining acceptable sensitivity:
1.
Set the sensitivity in both modes to less than 30.
2.
Ground Balance the machine manually in Motion All Metal Mode.
3.
Search in the Discrimination Mode with a discrimination setting higher than 25.
How Metal Detectors Work
Most metal detectors use VLF Induction Balance technology. Here's how they work:
The search coil (also called search head or loop) contains two electrical induction coils which
are like antennas. One coil transmits a rapidly alternating magnetic field, illuminating the region
surrounding the search coil. If metal is present, its electrical conductivity distorts the magnetic
field. If iron metal is present, its magnetism also distorts the magnetic field, but in a different
way, allowing the metal detector to distinguish between ferrous and nonferrous metals.
The other coil is a receiving antenna which detects changes in the magnetic field caused by
the presence of metal. Electronic circuits amplify this weak signal, analyze it to determine the
changes which occur as the search coil sweeps over the target, and then convey the
33
Comprehensive Operating Manual & Guide to Metal Detecting
PRO-ARC
22
PRO-ARC
Comprehensive Operating Manual & Guide to Metal Detecting
5
Fe
3
O
4
Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Battery Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Ground Balance (GB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Setting Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52-53
Backlight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
Frequency Shifting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54-55
Capabilities & Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..56-61
Tips & Techniques
Search Techniques
How to sweep the searchcoil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62-63
Boost and Cache Locating Processes . . . . . . . . . . . . . . . . . . . . . . . . . . .63-65
Pinpointing targets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65-66
Estimating target size and depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66-68
False signals and chatter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68-70
Ground minerals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70-71
Hot Rocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71-72
Adjusting Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
Tips on ground balancing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73-75
Shallow Water Hunting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Salt Water Hunting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
How metal detectors work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76-77
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Back Page
76
Search Techniques (continued)
SALT WATER HUNTING
Salt water is highly conductive, and produces a strong signal which is like that of metal. The
PRO-ARC is not specifically designed for high performance in salt water, but can be used in
this environment.
If you desire to search in or over salt water, the following measures will usually be sufficient to
silence the salt water response while retaining acceptable sensitivity:
1.
Set the sensitivity in both modes to less than 30.
2.
Ground Balance the machine manually in Motion All Metal Mode.
3.
Search in the Discrimination Mode with a discrimination setting higher than 25.
How Metal Detectors Work
Most metal detectors use VLF Induction Balance technology. Here's how they work:
The search coil (also called search head or loop) contains two electrical induction coils which
are like antennas. One coil transmits a rapidly alternating magnetic field, illuminating the region
surrounding the search coil. If metal is present, its electrical conductivity distorts the magnetic
field. If iron metal is present, its magnetism also distorts the magnetic field, but in a different
way, allowing the metal detector to distinguish between ferrous and nonferrous metals.
The other coil is a receiving antenna which detects changes in the magnetic field caused by
the presence of metal. Electronic circuits amplify this weak signal, analyze it to determine the
changes which occur as the search coil sweeps over the target, and then convey the
