Minelab EQUINOX 900 Instruction Manual page 31

Threshold Level
'TRUE' THRESHOLD TONE
When in Gold* Mode a 'true' threshold tone is used and is
ideal for gold detecting, especially for small nuggets�
Unlike the simplified 'reference' threshold tone that is used
by the Park, Field and Beach Modes, the 'true' threshold
is a continuous background tone that can be adjusted to
improve the audibility of faint signals and gives more target
information through changes in volume depending on
target signal strength and composition�
'True' threshold allows faint gold signals to be emphasised
in noisy soils� Greater control of the target audio response
may be achieved by adjusting the Threshold Level and
Volume Adjust settings together�
* EQUINOX 900 only
CONTENTS
(Continued)
Too Low
If the Threshold Level is too low, the slight variation caused
by a small or deep target may not be sufficient to hear�
Adjusting the level to below an audible level will ensure
silent operation but could mask the audio response from
small or deep targets�
Too High
If the Threshold Level is too high, faint targets will be
harder to hear above the Threshold hum�
Just Right
Adjust the Threshold Level to a faint audible hum� This will
emphasise variations in signal response which may indicate
the presence of a target� If the soil conditions change, the
Threshold Level may need further adjustment�
31
Audio range that
you are able to hear
Quiet signal
now inaudible
Threshold Level
Threshold Level
Audio range that
you are able to hear
Audio range that you
are able to hear
Threshold Level
Loud signal
Quiet signal Loud signal
masked just audible
Very loud
signal
Quiet
signal