The metal detector has been around for a long time, as its earliest development started in the late 1800's. It then saw greater advancement in 1920 when Gerhard Fischer patented the first metal detecting device. However, it was not until the 1960's that industries started adopting the use of metal detectors for advancement in their fields.
Uses mostly included prospecting for minerals, but later extended to security use at airports and prisons, archaeological use, and even treasure hunting. In modern civil engineering and domestic use, a metal detector can be applied to locate pipes, reinforcements, or electrical wiring in walls to help avoid drilling or damaging infrastructure by accident.
Regardless of the purpose for which you would use a metal detector, you will need to know how to operate its settings first. Modern detectors can work at greater depths and sensitivity than earlier models, but, to unlock its full uses, understanding its settings is important.
How Does a Metal Detector Detect Metal?
The most basic design of a metal detector works by converting direct current into alternating current by passing it through an oscillator. The current is then further fed into a coil to produce an alternating magnetic field. If a conductive metal passes through the magnetic field, it will induce eddy currents and produce its own magnetic field. Using a second coil, changes in the prime field can be detected.
Usually, the changes in the magnetic field are communicated to the operator by producing a sound. In modern development, Gerhard Fischer noticed that radio beams can be distorted by the presence of metals. He then invented his first detector based on using a search coil resonating at a radio frequency that could communicate any distortions it picked up. Modern manufacturers use their own patented technology to improve on these earlier designs.
How to Use a Metal Detector's Settings
No metal detector is the same, so it is advised to read the included user manual for accurate information on your device.
How to Use the Preset Programs
Beginners should essentially stick to the preset programs of your metal detector, if it has any. Most commercial models and domestic versions should include the basic programs discussed here. These models will offer you different sensitivities at which you can probe to either find all kinds or only specific types of metal.
Usually, the manual will contain all the indicator data that you’ll need to understand the tones at which your device operates. It is vital to know these, as lower tones will indicate a specific metal, and the changes will also communicate the distance. Manufacturers might vary how each is indicated, but this concept is mostly applied universally.
The 'All-Metal Mode' will detect every metal that could be present. It is best used for general probing when you are not out looking for specific metal. Knowing the tones at which each metal resonates is vital to operate this setting to its highest potential.
This mode will also probe at greater depth and will not be bothered by other materials that your detector finds. If you use this mode when combing the beach, don’t be surprised if you find a lot of buried cans and rubbish. The all-metal mode will not discriminate in what it is looking for.
‘Coin Mode’ will tune the detector to find iron and nickel, or any other metals present in coins and jewelry.
‘Relic Mode’ is a highly discriminate setting that will search for more substantial objects with bigger presences. It is used by archaeologists who are searching for lost and buried relics that might contain metals.
This mode is used if you are looking for gold. It will detect only the presence of gold in mineral deposits or in the ground.
Metal Detector Settings
You may find multiple buttons and dials depending on your device, but here are the most common settings you will find.
This toggles between the pre-set programs.
Sensitivity or Gain
This controls the amount of energy focused in the searching coil. Tuning this will improve or reduce your searching depth, but keep in mind that the more energy it focuses, the less sensitive it will be.
This is a useful feature that may not be included on every model. Pressing this button will switch from detecting an object to pinpointing its precise location.
This setting allows you to switch between discrimination to detect different metals.
This changes the volume setting of your headphones or speaker.
This is used if you want to hear a hum in the background that will help you find signals if there are multiple objects present. Note that not all devices come with this ability.
Adjusting this setting will customize the tones based on the conductive scale, and it will tell you the object’s conductivity by the sound produced.
Adjusting this setting will increase or reduce its conductive discrimination. Keep this setting low if you want to look for more metal types and want better search depth.
This setting will help you skip past objects that may be considered junk by accepting or rejecting specified VDI numbers.
Now you know how to use a metal detector's settings to help you find buried treasure and hidden relics!