Kellyco PULSE STAR II PRO, Instruction Manual

Page: 77 / 89

Anot her pos si bi li ty to re du ce the sen si ti vi ty is to turn AUDIO TUNE all
the way to the left. Now the "dead area" up to the start of the tick ing
noise has to be pas sed. Ho we ver, this me thod does not af fect the me -
ter and the LEDs for the me tal discrimination.
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 he ma tite. 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 ti ce ab le when lo we ring the se arch coil. The tick -
rate sig ni fi cant ly in crea ses even when the re is no me tal ob ject be low
the sur fa ce. As long as the dis tur bing ground is le vel, you can hold the
coil at the same dis tan ce from the ground and main tain a cons tant tick -
rate. The PULSE STAR II PRO can be tu ned by po si tio ning the coil at the
cor rect se arch height from the ground, and then pus hing the MODE
switch brief ly to RETUNE. The se ground ef fects will not re du ce the sen -
si ti vi ty, they just add an offset to the detection signal.
If re du ced sen si ti vi ty to iron ob jects and ot her smal ler ob jects is ac cep -
tab le, an in crea sed SAMPLING DELAY will also re du ce ground ef fects.
Hol ding the coil hig her helps to re du ce ground effects 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.
76
8 Interference