06/26/2026
This is response to someone looking to "Modify" her Tesoro Saber detector.
Hi Jacky; My name is Al Holden owner of Pro Stock Metal Detectors. I knew Tesoro's Founder,Jack Gifford as one of his long time dealers. I can't say we were friends because he was hard to befriend and had a short fuse and a little unpredictable. Of all the manufactures that I represented, he was the only one publicly angered to think anyone could improve on his designs. Often some folks would try, and then screw something up, and expect under the Tesoro life time warranty make it well again.
The best thing I can do for you, is explain how things work. The best way to understand metal detectors is to take you to their home to meet the family. Metal detectors are in the Radio Family and the metal detector's most well known brother is the Citizen's Band Radio "C.B. Radio."
Both the CB, and your Tesoro, work with antennas to send out a radio signal and the antenna also receives a return signal. The search coil is the detector's antenna.
Now, in both cases, the operator wants great performance. The CB operator wants to boast that he can hear and talk to the people far away, and better than the next guy. Legally he is confined by the law and limited to a output power of only 4 watts. But there are under the counter devices called Linear Amplifiers or "Kickers" that range from 50 to 1000 watts! Then you can talk to Mexico! But all this greater distance is related to greater power. That works with the CB all because you are pushing a radio signal through the air with very little resistance!
Now, the Metal Detector is also pushing a radio signal out, and here again we want it to go far as possible. But we are not pushing into the clear air, we are pushing into the ground! The ground wants to put up a fight. The trouble with most soil is, it has different conductive elements which will weaken and even block the radio signal.
The detector manufactures took into account every single obstacle that hindered the path of the radio signal and did whatever was possible to solve the problem.
The problem Jack was having was when someone tried to modify one of his detectors by boosting the output power, he knew that was the total wrong direction to go, to him, a well regarded electronics engineer, it was insulting!
I have people call me with claiming great success finding hundreds of copper pennies but they are puzzled that they rarely if ever find pre-1964 silver coins. Didn't people lose them? Or were they already found? They reason, "maybe the detector isn't sensitive enough?" so they turn up the sensitivity. That makes perfect sense . . . but it is wrong.
When the detector sensitivity is clearly too high, the detector will start to static or become unstable. If the detector is like that, even pennies are still detectable because that produce a strong target if they have been buried long. Copper corrosion starts within days and slowly gets worse producing what we call a "Halo" which gives the detector a stronger target. Silver in many ground conditions will not corrode at all making a very weak target. If the sensitivity level is too high the weak signal from the coin goes undetected. By turning the sensitivity down to a smooth stable condition the silver will be detected. In most cases the guy who is not finding the good stuff is trying to hard.
Jack knew clearly he could not build the perfect detector for everyone, and for everywhere. Different grounds respond better to different radio frequency. Where I am in South West Michigan our soil has very little conductive elements. Any detector that is very low frequency like 4 kHz or 5 kHz will go crazy deep! But my wife is from Iron County in the western UP where the ground is so mineral rich with iron, a low 4 kHz detector will not respond to a coin you can "SEE" with your eyes laying on the top!
But, a 12 kHz to 15 kHz Tesoro will work well in most any ground.
The thing is, the metal detector companies are working hard at competing with each other in the entry level, because they want to dominate on Amazon! This has become so fierce it has indirectly pushed Tesoro and Whites out of business.
Right now you can buy a Minelab Vanquish 360 with target number ID, Tone ID, real non motion pinpoint with changing pitch audio, rechargeable, and "Multi Frequency" waterproof to 16 feet!
For $250.00 with a 3 year warranty.
My friend dug a U.S. 2 Cent Piece at 9" deep with a V360 yesterday. Honestly this detector is 100 times better that your Tesoro Silver could ever be.
The best use for your detector, is it makes a great rental because it is so user friendly. Al Pro Stock Metal Detectors 269-685-1776
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