TDI SL a beginner-entry metal detector manufactured by USA company White Electronics , it is a low price detector
for detecting gold ores and various precious and non-precious metals.
TDI SL is a multi-purpose metal detector for many uses including the detection of natural gold ore
as well as small metal objects such as rings as well as the discovery of buried gold treasures of ancient civilizations.
TDI SL works using Pulse Induction technology, which offers the best performance of underground metal detection
and gives greater depth compared to other technologies.
The device is designed for the comfort of the prospector through the light weight and flexible design
to provide the prospector with a comfortable experience throughout the day
in the fields of search and beaches and in the parks.
TDI SL Features
Search Technology
As previously mentioned, the device relies on preferred Pulse Induction technology
for achieving greater depth and better sensitivity than the common VLF technology.
TDI SL and one electric coil used in the search coil as a transmitter and receiver at the same time
as this coil sends powerful, short electrical pulses and each pulse generates a very small magnetic field.
When this pulse is fades away, the polar magnetic field reverses and suddenly collapses,
this electric current lasts for several microseconds (one millionth of a second) and causes an electrical current to flow through the coil.
This current called the reflected pulse and lasts about 30 microseconds.
Then another pulse sent and the process repeated a number of times up to about 2600 beats per second in this device.
When this flow of pulses collides by a buried metal object such as a coin,
a magnetic field is generated in the metal body, the reflected pulses and the current passing through the coil are determined
by a metallic target and the user is alerted by sound tones.
Ground Balance
One of the main features of the TDI SL is its ability to achieve the ground balance of the mineralization value of the ground
while maintaining the depth provided by the use of pulse induction technology.
This is achieved using a differential technique where two of the dissolution samples are compared.
So the ground balance is adjusted by adjusting the values so that the two samples have the same response,
thus eliminating the ground signal.
Easy Settings Controls
TDI SL includes a set of keys and buttons to control different settings:
– Threshold
It is used to control the volume of the audio tone
– Power / Gain
It is used to control the power level of the receiving signals.
This knob key increases or decreases from 0 to 10 of the signal amplification value,
and is used to turn the device on or off (when the value is 0)
– Pulse Delay
This knob key allows control of the pulse delay time, in other words the time period
between two pulses, and the key values vary between 10 and 25 microseconds
– Target Conductivity
This multi-value key provides three options:
– High – Only
– Low Only
– All Target
Note that the function of this key canceled in the case of making the value of the GB
of the ground Off, and better to make the ground balance the value must be set to All Target
– Ground Balance
It is a circular key with 11 values (OFF to 11), use it to manually control the
value of the ground balance as explained previously
– Frequency
This key allows for a slight adjustment of the pulse rate of the coil , use it to
reduce the effect of any electronic interference that made by external electromagnetic sources,
such as radio stations, microwave, shortwave or electrical fences such as in prisons, power lines, lighting,
electric storms or other metal detectors used nearby.
Search Coils
With any conventional metal detection device, the search coil size selected with a trade between depth and sensitivity balance.
In short, the larger-sized coil gives greater depth to the larger targets but with a smaller sensitivity to the smaller metal targets.
In contrast, the smaller coil gives better sensitivity to the smaller objects but with less depth.
Gold nuggets detected by a metal detector from very small granules to a few hundred fines,
so a search coil that can provide depth and sensitivity would be ideal.
TDI SL uses a patented dual-field DF search coil that gives the user two different coils simultaneously.
The first and largest is the external coil suitable for the most deep-seated targets,
while the inner and smaller one is more sensitive to the small objects.
Jamal Marwan –
Reliable metal detector for hobbyists
Lightweight and compact, ideal for long hunting sessions
Limited Depth