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Ground Balance Leeway
In some ground here in the Victorian Golden Triangle, you can achieve proper GB anywhere in a 50
click range, whereas other areas (i.e. Maryborough, Western Australia), the GB needs to be spot on
Rising Pitch Targets
In very mild to mild ground, for rising pitch (small) targets use the highest GB number where the QED
is still in GB. This will enhance detection distance for rising pitch targets.
Falling Pitch Targets
in very mild to mild ground, for falling pitch (large) targets use the lowest GB number where the QED
is still in GB. This will enhance detection distance for falling pitch targets.
Changing Mode
After changing the Mode always perform a GB.
The following tables shows quite clearly how much the GB changed from mode 1 through to mode
15. Note that these figures were obtained with the QED prior to the 2019 upgrade.
BTW, the GB number is just a number for your reference, there is no mineralised ground scale like
the Richter scale for earth quakes
Detection Hole
The QED has a:
•
Rising pitch for short time constant (TC) targets (one side of the detection hole) and
•
falling pitch for long TC targets (the other side of the detection hole).
The hole typically occurs where the ground has a similar TC to the target, which will generate a poor
or fluffy target response and a loss of depth.
This can be simulated at home by using alfoil folded into a few layers and to end up at about 8”
square. Put the detector on an outside table, with the coil in a vertical position and setup the detector
as follows: (
Note figures for pre 2019 QED Upgrade
) MGB: 100; THS-B: 50; THS-A: 30; Gain: 1;
Low Mode (e.g. the lowest Mode for your coil; I used 3 with my coil).
Summary of Contents for PL3
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