The very first metal detector was invented by Alexander Graham Bell in 1881, however he didn't call it a metal detector. It was an electromagnetic device that he called "The Induction Balance." Unfortunately it was very crude and hard to use. About 45 years later in 1925 a man named Gerhard Fischar invented a portable device capable of finding buried objects. After a few years of making changes to it and perfecting it, the first metal detectors were sold to treasure hunting enthusiasts. Since then metal detecting has become a hobby for people of all ages who love setting out on treasure hunting missions.
During World War I, metal detectors were frequently used to detect mines or buried weapons. It wasn't long until metal detectors were adapted for use underwater to detect explosives (in cases of war) or for scuba divers in search of buried treasures. The early metal detectors were only capable of detecting metals about two inches underground. Most modern metal detectors are much more powerful and can detect small coins buried many feet deep and some detectors can go even further.
With so many metal detectors on the market, it's important to know what features you are looking for. Do you want a metal detector that you can submerge underwater at the beach? If so, then look for a waterproof one. If you're going to stick mainly to the sandy shoreline, then a water-resistant detector will probably suit you just fine. Are you interested in finding gold? There are detectors made specifically for locating hidden gold. If finding coins is more your thing, then a different detector is what you want. While some are designed for use in fresh water, others work better in salt water. They range in price from around $400 to over $1500 and the quality is reflected in the prices.
Today there are three main types of metal detectors available: VLF (motion) detectors, pulse induction detectors, and multi-frequency detectors. Depending on your needs and preferences, some detectors can be used for beach, land, and water hunting, and others offer features like better target volume control for hearing through a diver’s neoprene hood underwater.
VLF (Motion) Detectors: VLF stands for Very Low Frequency. These detectors are also known as motion detectors and are best suited for land and fresh water use, as they react to salt and become less reliable when the coil touches wet ocean sand.
Pulse Induction Detectors: Pulse Induction units are generally best in salt water because the pulse detectors are designed to ignore salt. These detectors pick up the deepest targets, don't require motion, and will continue to emit a steady tone when held directly over a target. If you're a scuba diving treasure hunter, this is a great unit for you!
Multi-frequency Detectors: Multi-frequency detectors are a little pricier than the other two types, but they deliver the best of both worlds. The units scan with multiple frequencies and can therefore adjust for the soil composition and mineralization of the area you're working in. Scuba divers also get some great use from these.
Target Alert: Metal detectors use one or more audio or visual alerts to let you know when a signal is acquired. Less expensive detectors will give off the same sound regardless of the metal detected, whereas more expensive models will use distinctive tones based on the type of metal.
Ground Balance: This setting allows you to adjust your detector to look for only certain minerals in the ground so there are less false alarms.
Detection Mode: This is a setting that can be changed based on the type of object you're looking for. The four most common detection modes are coin, coin/jewelry, relics (such as buckles, buttons, bullets, etc.), and prospecting (gold).
Sensitivity: Most models will allow you to adjust the unit so it is either more or less sensitive to minerals or targets in the ground and electrical interference. This will also cut down on false alarms while not allowing you to miss buried treasure.
Discrimination: This feature allows you to select which items you want to dig. This can be very helpful in eliminating trash and only digging better targets. This feature is great on land or dry sand.
Display: Many land/dry sand detectors have electronic displays that show information about the type of target you've found and the depth of the target before you start to dig. Generally, the more expensive the model, the nicer and more detailed the display will be.
Battery Life: Many metal detectors use common battery types such as 'AA', while some are rechargeable (no batteries). Running times can range from only a couple hours to over 30 hours of operation.
Other Metal Detector Features
- A portable shaft that folds down or collapses for easy packing and transporting
- There are waterproof and water-resistant units for shallow water detecting or scuba diving
- Salt and freshwater versatility
- Enhanced sensitivity to coins, gold, or silver
- Iron discrimination detectors
- Detachable control box with belt or chest mount
Drawing an X: This is a simple but effective technique when attempting to pinpoint in a discriminate mode or with a motion-only detector--such as the Tracker series and Quick Draw II. After receiving a signal, swing the coil a couple more times horizontally making sure it is a repeatable signal. Now swing the coil vertically at the same point you have determined the target to be attempting to draw an "X". When you have your signal centered on the crosshatch of the "X", the target should lay within a 5-inch circumference.
The Pendulum: Having your detector tuned to the Discriminate mode or if you're using a motion-only detector, raise your coil a few inches above the targeted area and wave it like a pendulum as you listen carefully for where the signal seems to be the strongest. Try drawing an "X" at the same height over the target making sure you have centered where the target is located. Now slowly lower your coil making sure you're still getting your strongest signal at the center of the "X".
Loop Cover: This looks like a Frisbee and snaps right onto your coil to protect it. Cost is usually around $7.
Headphones: For areas without much background noise, regular headphones or earbuds will work just fine. If you are in an area with a lot of noise around you, then opt for a larger set of headphones with ear cups that completely cover your ears.
Hunting Knife: A hunting knife will make digging up coins easy.
Electrician's screwdriver: Use it to pop up those shallow coins, and to carefully retrieve coins from the edges of holes.
Nail apron: Put your treasures in one pocket and junk in the other. Empty the junk in a trash can when you're done detecting for the day.
The best places to go metal detecting are simply where people have been. People drop things, leave things behind, and lose items as they swim, camp, play, and spend time in the great outdoors. Search the following areas for lost, forgotten, or hidden items:
- Picnic areas
- Recreational vehicle parks
- Amusement parks
- Carnival sites
- Swimming areas such as lakes and rivers
- Seaside beaches
- Sandy, dirty, or grassy parking areas
- Old home sites
- Old school sites
- Children's summer camps
- Fishing camps
- Hunting camps
- Under bleachers
- Under ski lifts
- Old military bases
- Old campgrounds
- Roadside produce stands
- Around any resort area
- Stock car speedway
- Small circus grounds
- Always gain permission when detecting on private property.
- Learn all of your state and federal laws and know how they apply to metal detecting.
- Dress for the weather!
- Wear protective gloves at all times when recovering metal objects.
- If you're detecting in an area where there is harmful wildlife or traffic, refrain from wearing headphones.
- Wear high boots to protect your legs from prickers, snakes, and biting insects.
- Attempt to be friendly and polite to all those you meet; make a good impression as a representative of the hobby.
- Bring sunscreen!
- A visor, hat, or sunglasses will increase visibility and prevent eye strain.
- When you find junk, dispose of it properly to help keep public spaces clean.
- Always be considerate of others when detecting.
Happy hunting, and let us know how it went in the comments below!