How it all began...
This metal detector has a long history--it didn't just pop out of the woodwork all of a sudden.
The story began in 1962, during a walk in the Mojave Desert, near Newberry Springs...
My friend George and I were working on a medical electronics project and staying at his mother's house--taking advantage of the free rent. (We had just started out in business and we were low on cash.)
One day, while walking on the desert, during a break from work, George pointed out the opening of a tunnel in a hill side: "That's the Silver Bell Mine", he said.
I had heard of silver and gold having been found in the desert. I had read the story of "Pegleg's Black Gold"--nuggets covered with a patina of "desert varnish", which made them look like ordinary, black rocks.
The prospect of instant wealth made me buy a metal detector as soon as we got back to Los Angeles. Bill Hays at the General Electronic Detection Company on Lakewood Boulevard in Bellflower had the very thing I needed.
The
Detectron Transmit/Receive metal detector was a state-of -the art detector and
sensitive enough to pick up the nuggets I expected to find on our next trip to
the desert.
The excitement was almost unbearable as we took off across the desert in search of gold. I had read somewhere that volcanic activity was linked to the process of gold being forced into crevices of fragmented quartz.
Signs of past volcanic activity were everywhere and as we approached a cinder cone, the metal detector made a loud noise...
The rock that set it off looked like a piece of lava. There was no gold visible on the outside, and scratching it with a knife confirmed that it was not "black gold", so I figured that the gold must be inside the rock...
Back in Los Angeles, I took it to an assayer. The result was very disappointing:
Apart from the common minerals, the rock contained mostly iron...
That was my first encounter with a "hot rock", and it was going to change my life,
and that of my friend George as well....
This is a picture of one of the
rocks we picked up on that fateful day. I know now that it's 
called
"andesite" and it's only one of the many kinds of hot rocks that make
life miserable for prospectors using metal detectors...
The project George and I were working on was an "Electromagnetic Flowmeter". The physics of eddy currents--the phenomenon responsible for making metal detectors work--was quite familiar to me. So, I decided to design a better metal detector--one that didn't detect rocks...
This was a part-time effort, but about four years later, I had finished the prototype of a detector that ignored magnetic minerals and naturally occurring magnetic "lode stones". Proud of my accomplishment, I demonstrated the detector to Bill Hays, who had sold me the Detectron. "You have just solved an industrial problem", Bill told me. He had received inquiries from a mining equipment salesman who couldn't find a metal detector that would not be affected by iron ore. The detector was needed to find "tramp metal"--lost shovel teeth and drill bits that traveled along with the ore and caused damage to the crushers.
I made coils big enough to reach across a conveyor belt, and we tried it at a mine at Eagle Mountain in the Mojave Desert.
To everybody's amazement, including mine, the detector worked. That was a beginning of the pulsed-field industrial metal detector in the U.S.A.
We subsequently tried it at mines in northern Minnesota and other places where conventional metal detectors made by RCA and Westinghouse did not work. A garage operation in Venice, California, had bested the industrial giants...
As often happens, when there is a potential of making big money, intrigue is sure to follow. I had filed a patent application for the detector, and since there was nothing similar on the market, I was sure there was no problem with infringement.
However, a geophysical surveying method developed in Canada used a similar technique for locating ore bodies from the air.
Not being familiar with the patent application process, I though that was the end and I abandoned the patent application.
That turned out to be a very bad move. The original contact to the mining industry, the salesman I thought was an ethical and reliable individual, took a detector to a company in Wichita to be reverse-engineered. Without a patent, there was no recourse. This man and a side-kick started a competing enterprise.
Divine justice intervened, however, and they both died, soon thereafter. That was one of the very few times I've laughed out loud when reading the obituaries.
The widows sold the detector to another individual, who was quite successful for a while, but he also died prematurely, a few years later. ( I should have told him about the curse...)
Installing metal detectors on conveyor belts is no picnic. It can be very hot, very cold and it's almost always very dusty, dirty and noisy. Traveling to the most inhospitable places in the country began to take a toll on me.
I sold out my interest and returned to medical electronics--a much more civilized endeavor. My friend George carried on with the metal detector, and I got involved in a consulting capacity, every now and then.
It was this involvement that brought me to a gold mine near Jamestown, California. We installed a tramp metal detector on a conveyor belt some time in 1991. It seemed to work normally, and we had no inkling of what was going to happen about a year later...