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Comprehensive Operating Manual & Guide to Metal Detecting
PRO-ARC
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Comprehensive Operating Manual & Guide to Metal Detecting
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Search Techniques (continued)
The Fe3O4 bar graph indicates how much iron mineralization is present. For it to work, the
searchcoil must remain in motion. The most accurate readings will be achieved by pumping
the coil as you do when ground balancing. The higher the mineralization, the greater the
necessity to ground balance the detector for the best depth performance.
If you are searching for relics, you can make a map of the soil of the site. Make a grid of the
site. Then collect data. Ground Balance to document mineral type; view mineral amount on the
Fe3O4 bar graph. Then plot the data on the site map and draw isolines. In this way you may
be able to locate areas which have been dug, backfilled or subjected to fire. This information in
turn helps to reveal the history of the site.
SHALLOW WATER HUNTING
All Fisher Research Labs searchcoils are waterproof, allowing you to search in shallow water
about two feet deep. If searching around water, be careful not to get the electronics housing
wet. Avoid salt spray, as it will work its way into the control housing and damage the
electronics -- such damage is not covered by the warranty.
The electrical conductivity of the water itself can pose some challenges. You may get false
signals when going into and coming out of the water, making it necessary to pay careful
attention to keep the coil either in or out of the water, but not to touch the surface. This effect
may be observed in either fresh or salt water.
6
Specifications
Mechanical:
S-rod with electronics housing mounted on handgrip, 3-piece
breakdown, batteries under elbow, 2-way armrest adjustment -
forward/backward & around forearm.
Searchcoil:
11” (28 cm) open-frame elliptical double-D, waterproof.
Batteries:
4 AA, alkaline (included).
Weight:
3.5 pounds (1.6 kg) with alkaline batteries installed.
Static Balance:
force in vertical plane normal to elbow 0.47 pounds (0.22
kg).Varies with adjustment and user's stance and arm/hand
physiology.
Dynamic Balance:
axial moment, 0.29 foot-pounds (0.39 newton-meters). Varies with
adjustment and user's stance and arm/hand physiology.
Sweep Effort:
lateral moment 5.2 foot-pounds (7.1 newton-meters).
Operating Principle:
VLF induction balance
Operating Frequency:
nominal 13 kHz, quartz crystal timing reference 13158Hz,
13100Hz, 1043Hz, 12987Hz, 12931Hz, 12876Hz, 12821Hz
33
Comprehensive Operating Manual & Guide to Metal Detecting
PRO-ARC
22
PRO-ARC
Comprehensive Operating Manual & Guide to Metal Detecting
75
Search Techniques (continued)
The Fe3O4 bar graph indicates how much iron mineralization is present. For it to work, the
searchcoil must remain in motion. The most accurate readings will be achieved by pumping
the coil as you do when ground balancing. The higher the mineralization, the greater the
necessity to ground balance the detector for the best depth performance.
If you are searching for relics, you can make a map of the soil of the site. Make a grid of the
site. Then collect data. Ground Balance to document mineral type; view mineral amount on the
Fe3O4 bar graph. Then plot the data on the site map and draw isolines. In this way you may
be able to locate areas which have been dug, backfilled or subjected to fire. This information in
turn helps to reveal the history of the site.
SHALLOW WATER HUNTING
All Fisher Research Labs searchcoils are waterproof, allowing you to search in shallow water
about two feet deep. If searching around water, be careful not to get the electronics housing
wet. Avoid salt spray, as it will work its way into the control housing and damage the
electronics -- such damage is not covered by the warranty.
The electrical conductivity of the water itself can pose some challenges. You may get false
signals when going into and coming out of the water, making it necessary to pay careful
attention to keep the coil either in or out of the water, but not to touch the surface. This effect
may be observed in either fresh or salt water.
6
Specifications
Mechanical:
S-rod with electronics housing mounted on handgrip, 3-piece
breakdown, batteries under elbow, 2-way armrest adjustment -
forward/backward & around forearm.
Searchcoil:
11” (28 cm) open-frame elliptical double-D, waterproof.
Batteries:
4 AA, alkaline (included).
Weight:
3.5 pounds (1.6 kg) with alkaline batteries installed.
Static Balance:
force in vertical plane normal to elbow 0.47 pounds (0.22
kg).Varies with adjustment and user's stance and arm/hand
physiology.
Dynamic Balance:
axial moment, 0.29 foot-pounds (0.39 newton-meters). Varies with
adjustment and user's stance and arm/hand physiology.
Sweep Effort:
lateral moment 5.2 foot-pounds (7.1 newton-meters).
Operating Principle:
VLF induction balance
Operating Frequency:
nominal 13 kHz, quartz crystal timing reference 13158Hz,
13100Hz, 1043Hz, 12987Hz, 12931Hz, 12876Hz, 12821Hz