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INLAND an DISC MODE SWITCH
With INLAND selected the 990XD operates at a fixed level of ground exclusion.
This INLAND ground exclude point is factory set on the 990XD. All metal targets will
produce an increase in audio volume in this mode regardless of the ‘level’ control
setting. The ‘beach/disc’ detector remains operating and can be selected to drive
the meter or control the audio pitch by selection on the ‘disc mode switch’. The level
of discrimination of the beach/disc detector can be adjusted by the ‘level’ control.
The INLAND mode is used on mineralised inland sites and can be used in
conjunction with any one of the disc modes described below.
- By selecting METER DISC mode the meter needle moves to the right for good
targets and to the left for reject targets.
- By selecting METER + AUDIO DISC mode the meter moves to the right for good
targets and to the left for reject targets, and the audio pitch increases for good
targets and decreases for reject targets.
- By selecting NONE the meter needle moves to the right for all targets and the pitch
remains constant.
BEACH an DISC MODE SWITCH an LEVEL control
Due to the varying nature of beach soils (the salinity and wetness) the 990XD is
equipped with an adjustable level of ground exclude in ‘beach’ mode. It is the mode
best suited to beach detecting where fine adjustment of the ‘level’ control is required
to exclude wet sand.
- By selecting ‘meter disc’ mode the meter needle moves to the right for good targets
and to the left for reject targets.
- By selecting ‘none’ the meter needle moves to the right for good targets and to the
left for reject targets (same as meter disc since it is in beach mode).
- Selecting ‘meter + audio disc’ gives a pitch increase to good targets, reject targets
are ignored. The inland detector plays no part when ‘beach’ mode is selected and is
switched off. Only use this beach mode on the beach or at inland sites where there
is no mineralisation and where you do not wish the detector to sound off over iron.
It should be apparent from the above that the ‘level’ control acts primarily as
ground exclude control in ‘beach’ mode, and secondly varies the discrim point
when operating in ‘meter disc’ or ‘meter and audio disc’ mode.
BATTERY CHECK
A battery condition indicator is provided on the detector. Turn the power on/off, tune
control on. Turn the Level control fully anti-clockwise to the battery check position.
The meter will indicate in the green battery symbol area if the batteries are good.
Rechargeable batteries will not read as high into the green as standard batteries
even when fully charged. They also give less indication of discharge on the meter
during use. Remember to switch out of ‘batt check’ when you have checked the
batteries.
Operating Instructions
