Iron Cancel (Discrimination); Iron Cancel Adjustment - White's GARRETT GOLDMASTER 24k User Manual

Disc Setting
(2 bars)
Iron Cancel (tap)
Disc. Adjust (hold)

Iron Cancel Adjustment

To enable Iron Cancel in either Beep or Zip mode,
tap the Nail Icon. This will engage the Iron Cancel
feature at the default setting. You can adjust this
setting up or down by holding the Nail Icon, then
using the Up and Down buttons to set the discrim-
ination range. Best practice is to only use what is
required for smooth operation of the GM24k, as
too high of an Iron Cancel setting will decrease the
detector's sensitivity to small gold nuggets. Again,
this is a trade off—it is up to the operator to pick
the balance between a smooth threshold and max-
imum sensitivity. If you are getting a lot of high
signals from hot rocks, tap the LOCK button while
in the Iron Cancel adjustment mode. This will
block out a range of signals from 94-99.

Iron Cancel (Discrimination)

When detecting for gold nuggets, it is often
best to "dig it all. " Gold can have various sizes,
shapes, and be embedded in iron rock, so it is
nearly impossible to account for every nugget
in the ground and only dig gold. However, in
challenging conditions the electronic prospec-
tor may need to adjust the GM24k to cancel out
unwanted targets or heavy ground mineraliza-
tion.
This is done at the expense of full sensitivity,
but in extreme conditions the amount of sig-
nals can overwhelm your senses, causing "ear
fatigue. " In these cases the real battle is in find-
ing good targets, not raw depth. Situations
where you might need to use Iron Discrimi-
nation are: rapidly changing ground minerals,
high concentrations of hot or cold rocks, old
mining camps with iron trash, and highly vari-
able ferrous ground conditions.
Please note that unlike coin detectors, the thresh-
old will not go silent over discriminated targets
in the "Zip" (VCO) audio mode. This is to ensure
smooth operation and combat ear fatigue. You may
find that it is best to detect with Iron Cancel off,
and then toggle it on to check a target. Very small
gold will often report a very weak Target ID num-
ber, or none at all, so this setting is best used as a
last resort in only the most challenging conditions.
Goldmaster 24k User Manual
GM24k Controls
13