JMT Metal Detectors JMT Metal Detectors

Tesoro Cortés Metal Detector


The Cortés represents the best combination of current and new technologies
that Tesoro has to offer. When Jack Gifford and Vince Gifford set out to create
a new target ID machine they each brought with them different experience. Jack
has over twenty-five years experience designing some of the best analog
detectors that have been on the market. Vince brought with him a decade of
computer systems experience. Together, they have been creating new technology
that gives our detectors superior performance and keeps them easy to use.
Various parts of this technology have been finding it's way into Tesoro
detectors since the introduction of the Golden µMax. The new Cortés represents
all phases of our new microprocessor technology combined with our tried and true
analog circuits to create a detector that has all of the high end features our
customers have asked for with user friendly Tesoro controls.

The first thing that you will notice is the control box and battery holder
configuration. The µMax housing was just not big enough to hold the new circuit
board so we moved the batteries down under the arm bracket and increased the
size of the box slightly. This allows us to use a 12 volt system to work with
the demands of the target ID circuitry. It also gave us the ability to put a 2¼"
speaker on the Cortés. This will give better and louder target signals in the

The Cortés' 2x16 character LCD display will catch your eye as well. This area
is the information center of the detector. The top row is an alpha/numeric
display that gives a broad indication of your possible target. One of five
different categories are displayed. Also if the target is overdriving the
circuits, the display will tell you to lift the coil for a more accurate
reading. The alpha/numeric and bar graph section of the display will remain
blank until the coil passes over a target. After the detectorist has decided to
dig or ignore the target the display will clear itself after six seconds of not
receiving a signal. The display works in all modes, regardless of the
discrimination setting. By clearing the display after six seconds the user is
able to tell if has passed over a new target that may have been discriminated
out. The detector may not produce an audio signal, but the display will show a
target reading. The detectorist then has the choice to either go back and check
the target or ignore it.

The bottom half of the display contains the real nuts and bolts information
that will help you to work the Cortés to its fullest extent. The far right hand
part of the display is a battery level indicator. This gives an accurate measure
of your current battery level. On the far left-hand side is the probable depth
indicator. The Cortés uses the phase shift of the target to determine the
probable target and then looks at the amplitude of the signal to determine the
depth. For example: a nickel and a quarter are in the ground and the quarter is
deeper than the nickel; if we just went off of amplitude change, the detector
may read the two targets as being the same depth. However, the Cortés would show
the quarter as being deeper because its phase shift response is different than
that of the nickel.

In the center of the lower display is a nine segment bar graph display. The
different segments represent the following possible targets: iron; foil: nickel;
round tab; square tab; zinc penny; copper penny and dime; quarter; half and
dollar. The graph shows what the coil saw during the entire sweep of the coil.
The targets metal composition and orientation in the ground can cause "smearing"
or possible indication in more than one graph segment. For example: pull tabs
usually will not respond in a single segment but give signals in two or three
segments. To help the detectorist decide on the target, we have also included an
ID Number display next to the bar graph.

The ID Number takes the largest part of the signal and converts it to a two
digit number. When Vince put together the scale for the ID Number, he decided to
put the most resolution in the middle range of targets. This is the area where
nickels, pull tabs and gold rings lie. We know that iron will always be on the
low end of the scale and silver coins and jewelry will always be on the high
end. So iron targets will always give a reading of 0 and silver will always give
a reading of 95. The Cortés now gives you the ability to decide what you want to
dig. One of the hardest parts of designing detectors is the fact that pull tabs
can vary from place to place. But a hunter working in the same area can use the
ID Number to learn the characteristics of the local pull tabs and effectively
ignore them.

For those detectorists that prefer a notch filter discrimination, we have
also added a simple flip switch to activate either a narrow or wide notch
window. When the display is blanked, two "N"s or three "W"s will appear on the
screen. The N will indicate a narrow notch window and will be in the round tab
and square tab portion of the graph segments. The wide notch window will cause a
W to be in the round tab, square tab and zinc penny segments. These indications
are an easy way to check what part of the scale is being notched out. The notch
indicators will only show when there is no target under the coil. When there is
a target signal, no matter if the target has been discriminated or not, the
display will show the information of the target.

The Sum mode is another feature to help identify targets. While the detector
is in either the Discriminate or All Metal mode, the display shows the target
information from the entire sweep of the coil. Each time the coil passes over
the target the microprocessor generates a new target ID reading. While this is
nice for general searching, it can be confusing while pinpointing. This is where
the Sum mode becomes useful. Pushing the springloaded switch into the Sum mode
causes the detector to start a multi-tone ID and averages all of the coil passes
over the target. The tone ID has nine different tones and relates directly to
the bar graph segments. The higher up on the graph the target is, the higher the
pitch of the audio signal. Averaging the coil passes over the target gives the
detectorist the ability to get rid of most of the signal noise that prevents
making an accurate target identification. Here's how it works: when the
detectorist gets a target signal that he wishes to check out, he pushes and
holds the Mode switch in the Sum position. Shortening his coil sweep to only a
two or four inch sweep he passes the coil over the target three to seven times.
The short multiple sweeps give the microprocessor the chance to sum the passes
and average them. During the sweeps the audio ID will start at the lowest signal
and will get progressively higher in pitch until there is no more change. When
this happens the detector is giving the most accurate ID possible. Then the user
can decide if he wants to dig or ignore the target.

All of these new features are complimented by Tesoro's easy to use controls.
No touch pads or scroll through menus. Set the detector how you like it by
adjusting the knobs on the front of the machine. The Cortés features an On/Off
Sensitivity knob; a Discriminate Level knob; a Manual Ground Balance knob; a
Mode Switch with All Metal, Discriminate and Sum mode settings; a Notch Width
switch with Off, Narrow and Wide settings and a Light switch to control the LCD
backlight with a High, Low, and Off positions.

The Cortés fits into a package that weighs just less than three pounds
(including the batteries!) and is covered under Tesoro's Lifetime Warranty. The
Tesoro Cortés makes target ID easy and fun. Contact your local dealer or the
factory for more information.

Operating Frequency10 kHz
Searchcoil TypeConcentric
Searchcoil Size9 x 8
Searchcoil FamilyEpsilon
Cable LengthApprox. 3'
Audio Freq. Target ID TonesApprox. 350 to 800 Hz
Audio Freq. All Metal VCOApprox. 350 to 920 Hz
Audio Output2 ¼" speaker and headphone jack
Headphone Compatibility¼" stereo plug
Weight (may vary slightly)2.98 lbs
Battery RequirementEight AA (alkaline)
Battery Life (typical)10 to 20 hours
Optimum Temp. Range30° to 100° F
Optimum Humidity0 to 75% R.H.
Operating ModesSilent Search Discriminate
No Motion All Metal
Notch Narrow/Wide