10 F1A4 Operator Instructor Notes and Syllabus
Minelab Countermine Division
Safety through Excellence
Twenty four
Multi Period Sensing.
The F1A4 uses three channels in its electronics comprising two target channels and one
ground channel. MPS successfully and easily detects the presence of mineralized
ground and ignores its effects. MPS can be a difficult concept to explain. It is
recommended that instructors make best use of PowerPoint presentation.
MPS produces a series of wide and narrow pulses that are transmitted into the ground
from the Monoloop. Note: it is a physics law that the electromagnetic radiation will also
transmit upwards in the opposite direction. That is why there can be no metal in the
Lower Shaft assembly.
Twenty five
After each pulse, both wide and narrow, a piece of metal in the ground will be “excited”
and will return its own radiation as a decay pattern as shown.
