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While the Lobo is useful as a coin hunter, it was designed as a nugget hunter, so the extra power available makes its
GROUND ADJUST tuning one of the more critical settings you must make to obtain proper operation of the detector. Also, in
most areas that will yield gold nuggets, you will be plagued by false signals caused by "hot rocks". Most of these false
signals can be minimized or eliminated by constant attention to the GROUND ADJUST setting. Since the mineralization will
change sometimes quite drastically within a few feet, you may need to readjust the control very often to maintain the proper
tuning.
To achieve maximum performance from your Lobo, be sure to properly adjust the GROUND ADJUST and THRESHOLD
controls in the ALL METAL mode. The settings of both of these controls will also affect the operation of the detector in the
DISCRIMINATE mode, so be sure to adjust them properly, even if you are going to hunt only in the DISCRIMINATE mode.
TUNING IN THE AUTO TUNED MODE
1. Put the Auto Tune/Mode Change Switch in the Auto/All Metal position and the Sensitivity control on Max. Make sure
that the threshold adjust gives just a weak beginning of sound.
2. Rapidly lower the searchcoil from about one foot above the ground to about two inches above the ground. Listen to
see what effect this has on the threshold sound. If there is no change, you are properly tuned. If the sound decreases as
the coil is lowered, and then comes back to threshold as the auto tuning recovers, you should turn the Ground Adjust
control about one half a turn clockwise. Repeat the step of lowering the coil rapidly again. If the sound increases before
the auto tuning recovers, you will need to turn the Ground Adjust control about one half a turn counterclockwise. Repeat
the step of lowering the coil rapidly again.
3. Keep repeating the lowering of the searchcoil, and making such adjustments to the Ground Adjust control until the
response is reversed. Then turn the Ground Adjust control back in small increments until you find the setting where there
is not a change in the threshold sound as the searchcoil is lowered toward the ground.
4. You are now tuned properly, and only need to begin your search. Keep monitoring the tuning by raising and lowering
the searchcoil every so often. Readjust the Ground Adjust as necessary to keep the detector properly tuned.
TUNING IN THE NORMAL MODE
1. Put the Auto Tune/Mode Change Switch in the lower position, with the Sensitivity control in the Max position. Be
sure that the threshold control is adjusted to just yield a faint beginning of sound signal. Hold the searchcoil about one
foot from the ground, and if the threshold has changed, momentarily lift the Mode switch to retune back to threshold.
Then lower the searchcoil to about two inches above the ground. Remember that you cannot hear the Threshold sound
while the Mode switch is in the Retune position.
2. If there is no change in the threshold sound, you are properly tuned. If the sound increases or decreases, it will not
recover automatically as it did in the Auto Tuned mode. If the sound decreased, turn the Ground Adjust control about one
half turn clockwise. If the sound increased, turn the Ground Adjust control about one half turn counterclockwise. When
you turn the Ground Adjust control, the threshold sound may get either louder or go quiet. That's normal, and means
nothing to the tuning procedure.
3. Move the searchcoil back up to about a food above the ground, and momentarily push the Mode switch into the
Retune position to reestablish the threshold sound. Repeat the step of lowering the searchcoil to the ground. Readjust
the Ground Adjust control as indicated by the change in the threshold.
4. When the threshold change reverse, then move the Ground Adjust control back in small increments, until there is no
change as the searchcoil is lowered towards the ground. Remember to momentarily hold the Mode switch in the Retune
position each time just before you lower the coil to the ground.
NOTE: The Normal mode of operation has very slow automatic retuning which is just fast enough to help you maintain the
threshold sound as you search. This slow autotuning is necessary because of the extreme power of the Lobo circuitry.
TUNING IN THE DISCRIMINATE MODE
Tuning the Lobo for use in the discriminate mode requires that the All Metal Mode tuning procedure be properly
accomplished, as the Ground Adjust control provides for mineral free operation in both the all Metal and Discrim modes. Also,
the threshold setting of the Tuning control determines the minimum sound level for deep targets in the Discriminate mode. Too
little threshold, and depth will be lost. Too much threshold, and the detector may become erratic.
After the All Metal mode procedure is accomplished, the only setting necessary for operation in Discriminate mode is set
the Disc Level control to the desired amount of trash rejection, and to set the Disc Sensitivity control to the maximum setting
that will allow smooth operation.
SELECTING THE PROPER MODE OF OPERATION
The Lobo offers two basic modes of operation, the All Metal mode and the Discriminate mode. Both modes are mineral
free if the unit is properly adjusted. The Normal mode is the industry standard "VLF" type which does not require motion of the
searchcoil for proper operation. This mode, while requiring an initial ground adjust setting of sound threshold, offers two very
important advantages, these being the ability to pin point without motion, and to provide exact ground canceling. The
Discriminate mode is based on motion of the searchcoil, but requires very little motion, and offers the advantage of completely
silent operation.
Nugget Hunting requires using the All Metal mode, since the response to small gold items is so close to iron.
We feel that for most nuggetshooting use, Auto Tuning will provide the best performance. Since most gold nuggets are
quite small, you need to be sure that your detector is tuned to threshold at all times to avoid missing any of these little
nuggets. Obviously the Auto Tuned mode will help you in this respect. Hot Rocks will cause a momentary silence as the coil
is swept over them, with a loud overshoot when the coil clears them. The sound is so different from a good target sound, that
it's very easily recognized. The only problem with just ignoring these sounds are that a small nugget may be hiding beneath
the hot rock. Adjusting the ground Adjust control in the clockwise direction until the hot rocks are almost neutralized will help
detect small gold nuggets, but the ground will read as a positive signal, so you will have to be very careful to keep your coil
height constant.
Normal Tuning is very useful for pinpointing, since searchcoil motion isn't necessary. This mode is also useful for
searching and for identifying whether a sound is target or the overshoot from an intense mineral signal such as a hot rock.
This mode is going to require much more care and attention from you also, since you will need to retune the detector more
often to maintain threshold, and you will also need to readjust the Ground Adjust control more often.
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