Ground Error - Omega 8500 Owner's Manual

GROUND ERROR

* When the detector's internal Ground Setting is lower than the actual
phase of the ground, the bars on the bottom of the graph will be
illuminated. The bigger the error is, the more bars will show up.
* If the Ground Error exceeds the level of three bars,
indicating the maximum error has been reached, and action must be taken
to adjust the Ground Setting.
To maintain maximum detector performance, keep the Ground Error to a
minimum by adjusting the Ground Setting.
Before making an adjustment, it is best to verify the Ground Error as follows:
1. Place the detector into All Metal Mode.
2. Pump the searchcoil up and down over a patch of ground free of metal,
repeatedly moving the coil to within 1" of the ground and lifting it up about
6" over the ground.
If bars appear at the top of the graph, manually adjust the Ground Setting
negatively until all of the bars disappear. If bars appear at the bottom of the
graph, manually adjust the Ground Setting positively until all of the bars
disappear.
While in ALL METAL Mode, pumping the searchcoil over the ground, you will
also hear audible evidence of an out-of-adjustment Ground Setting. If the
Ground Setting is too low, there will be a difference in the sound as the
searchcoil is moving away from the ground. It will sound like you are pulling
the sound out of the ground. If the Ground setting is too high, it will sound like
you are pushing the sound into the ground.
• If the sound is louder as you raise the searchcoil, manually adjust the
ground setting to increase the ground balance setting.
• If the sound is louder as you lower the searchcoil, manually adjust the
ground setting to reduce the ground balance setting.
If bars
appear
AT TOP
AT TOP
AT BOTTOM
AT BOTTOM
NO BARS
continued)
GROUND ADJUSTMENT CHART
or in Auto-Tune
pumping coil sounds like
PUSHING SOUND
OUT OF GROUND
PULLING SOUND
INTO GROUND
SAME SOUND
WHEN RAISING
AND LOWERING
or will appear,
then
DECREASE THE GROUND SETTING
INCREASE THE GROUND SETTING
NO
ADJUSTMENT
NECESSARY
21