False Signals And Chatter - Teknetics T2 Operating Manual And Manual

SEARCH TECHNIQUES (continued)
Estimating Target I.D.
With a single sweep over a target, you will usually see a 2-digit target ID displayed on the LCD.
Repeated sweeps back and forth over the target may cause the 2-digit target ID values to change
with each sweep of the coil; this may seem inconsistent with your discrimination setting. These
variations and inconsistencies provide important clues regarding the identity of the buried object.
Most metal detectors have difficulty properly identifying steel bottle caps, and the T
exception. Steel bottle caps will often read in the coin range, at the high end of the scale.
The ID number you receive from a buried coin will usually be consistent regardless of sweep
speed or angle. The readings from a steel bottle cap will tend to bounce around a lot more,
especially with variations in sweep speed or angle. By paying attention and taking this into
account, you can minimize the number of bottle caps you dig.
The visual ID and the discriminator are independent systems which analyze different sets of
signals. Therefore what you hear, or do not hear, provides additional information regarding
target ID. For instance, if discrimination is set at 40, and most sweeps result in no visual
target ID, the target is most likely iron even though the majority of the ID numbers will be
greater than 40.
The T 2 has a tendency to up-average nonferrous targets in the proximity of iron, indicating ID
numbers higher than would be obtained in an air test. This tendency is connected with the
T 2 's enhanced see-through ability – that is, the ability to find valuable targets in an area where
there is a lot of iron trash.

False Signals and Chatter

At times the detector may beep when there is nothing there, or it may seem like there is
nothing there. There are five major causes for this: electrical interference, nuisance buried
objects, ground minerals, hot rocks, and sensitivity set so high that internal circuit noise is
audible. The problem can usually be corrected by reducing the sensitivity setting, but
sometimes other measures can also be taken.
ELECTRICAL INTERFERENCE
Electrical Interference can be caused by power lines, appliances, computer equipment, cell
phones, fluorescent and vapor type lamps, household light dimmers, other nearby metal
detectors, electric fences, radio transmitters, and electrical storms. If you get abnormal noise
while holding the searchcoil motionless in the air, the cause is electrical interference or internal
circuit noise. By walking around with the metal detector, you can often follow the signal and
track it back to the offending device; simply turn the device off, or come back at another time
when it may be off. If the interference is from power lines, you might try another time of day.
Interference on power lines is usually caused by something connected to them which may be
idle in the evenings or on weekends. If the interference is from a communications or
broadcast transmitting antenna, reducing the sensitivity is usually your only recourse.
The T 2 allows you to shift operating frequencies to avoid electrical interference. See the
Frequency Shifting section on page 20 for information about this technique.
Comprehensive Operating Manual & Guide to Metal Detecting
TEKNETICS
2 is no
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