Pulse Star II pro Bedienungsanleitung Seite 77

8 Interference
AUDIO TUNE
An other pos si bil ity to re duce the sen si tiv ity is to turn all
the way to the left. Now the 'dead area' up to the start of the tick ing
noise has to be passed. How ever, this method does not af fect the me -
ter and the LEDs for the metal dis crim i na tion.
Ground mi ne rali za ti on
Com pared to VLF-IB de tec tors, pulse in duc tion metal de tec tors like the
PULSE STAR II PRO are much less af fected by iron min er als. How ever,
there is one min eral which ex hib its so-called mag netic vis cos ity, and
that is maghaemite. A high con cen tra tion of this min eral can even
cause a sig nal from the PULSE STAR II PRO.
This type of soil is no tice able when low er ing the search coil. The tick -
rate sig nif i cantly in creases even when there is no metal ob ject be low
the sur face. As long as the dis turb ing ground is level, you can hold the
coil at the same dis tance from the ground and main tain a con stant tick -
rate. The PULSE STAR II PRO can be tuned by po si tion ing the coil at the
MODE
cor rect search height from the ground, and then push ing the
RETUNE
switch briefly to . These ground ef fects will not re duce the sen -
si tiv ity, they just add an off set to the de tec tion sig nal.
If re duced sen si tiv ity to iron ob jects and other smaller ob jects is ac -
SAMPLING DELAY
cept able, an in creased will also re duce ground ef -
fects. Hold ing the coil higher helps to re duce ground ef fects as well.
Using the uni ver sal se arch loop des cri bed in chap ter 4, a com pen sa ted
se arch coil can be built up which re du ces both elec tro mag ne tic in ter -
fer en ces and ground ef fects.
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