36
FINE TUNING EXERCISE
An exercise to
show how
Threshold A
(Volume) and
Threshold B (Bias)
work/interact.
•
Attach a small coil, 8” diameter or less.
•
Obtain a small shotgun pellet or similar size nugget and a $1
Australian coin.
•
Set:
o
MODE to 1
o
GAIN to 4
o
THS-A (Volume) to 30, and
o
THS-B (Bias) to around NULL.
•
Ground Balance the detector.
•
Make certain there are no metal targets in the ground and place the 2
targets about 3 feet apart.
•
Swing over both targets and note the signals.
•
Reduce THS-B until the threshold audio signal volume is as high as
tolerable and swing coil over both targets again. You will notice that
the small target signal will be enhanced when compared with the
previous signal response.
•
Increase THS-B through and past the null point until the threshold
audio signal volume is as high as tolerable and swing coil over both
targets again. You will notice that the large target signal will be
enhanced when compared with the previous signal response.
•
Set THS-B to NULL and raise THS-A until the threshold audio signal
volume is as high as tolerable.
•
Swing over targets again.
•
Increase MODE and GB then repeat entire procedure and taking note
of which MODE number gave the best result.
Summary of Contents for PL3
Page 56: ...56 NOTES...
