It is possible. But you have to
adjust the gap between detector and the hole
while checking the output waveform from MP-981
using oscilloscope etc.
(It might be not as same as the gap condition which is written in the instruction manual.)
Please adjust the gap to obtain the output waveform as follows:
Lo (0.5 V or less) : at
around the hole area
Hi (Approx. 4.5 V) : at the area except for the hole
However, the output waveform
will not always become as same as the above
because the magnetic circuit might be affected
due to the mounted environment.
For example, when the MP-981 is mounted near a wall or Hi level voltage is output as a one-shot.