Selective Metal Detector SOREX PRO. Operating manual.
AKA LLC +7(495)623-4026 621-0481 http://aka.2000.ru [email protected]
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The appropriate symbol (E) is shown in the bottom right corner of the display when the
"Economy" mode is on).
EMI filter (electromagnetic interference).
The search near sources of electromagnetic
interference is a common problem (overhead lines, pipelines
equipped with cathodic protection and so on). There are many
FS in such areas and the sensitivity of the device has to be
reduced with all the circumstances that follow. EMIF is
intended for the neutralization of such FS with the sensitivity preserved.
Set up the adequate filtering in the following manner: Increase this level gradually and
get comfortable hearing FS minimum from the EMI. Remember that excessive level of
EMIF may miss small targets and slow down device operation.
Ground balancing
Device ground balancing is the most important aspect of the device search
settings. Incorrect balancing may reduce search capabilities of the device, causing
unstable operation and false responses.
Brief description of the procedure. Each object has its own shape, conductivity
and magnetic compound, all of them are assumed to be VDI (Visual Digital Index). We
remind that VDI is an angle preference, its number equals to the inclination of the signal
vector (hodograph on the device display) from the vertical axis. The ground, depending
on the mineralization level (presence of iron oxides), covers target signal with its own
signal, changing its VDI till it "converts" small and deep targets, as well as large targets
made of high conductivity metals (copper, silver, aluminum), into the "iron". The
accurate detector ground balancing in the search area is performed in order to reduce
the ground influence to the minimum. Major balancing purposes:
1.
To make the ground "invisible" for the device, i.e. avoid phantom signals
from the ground with no targets in it.
2.
Set up correct (standard) reference system for VDI. Accurately balanced
device must cut-out ground signal mathematically and identify the target
correctly getting joint signal from target and ground.
It should be noted that during "air tests" the balanced device will keep making
correction for the ground ... which is not available at the moment. During an "air" test it
may lead to an "invisible" large aluminum or copper object (pan, 5 kopeks of Catherine II),
if the ground has got too deep into "plus". And if this "too deep" is too big, those targets
may be detected as "iron" ... and the tester might get very frustrated. Or, to the contrary,
it would decrease VDI of those targets, when balance gets too deep into "minus", and
sensitivity to them "in the air" goes up incorrectly ... resulting in unreasonable happiness
and hopes of the tester.
Memorize a simple formula: One degree of balance phase change gives VDI
change for all targets by the same one degree to the change direction (+ or -). I.e. if you
have 5 kopeks of Catherine II detected as "iron" "in the air" with VDI -86 instead of
