About seven years ago, a brain scientist was working with primate brain signals three floors underground. The scientist was using special neurological amplifiers that amplified micro-volt signals. He called me to solve a strange, sporadic noise problem that had appeared in his amplifier outputs.
His laboratory had been in operation for many years before this problem appeared. When confronted with a mysterious problem, I always ask one particular question: "What is changed, what is different?" But in this case, the answer was nothing.
Connecting up a scope, I soon saw a signal on the screen that coincided with a noise from a speaker connected to a neural amplifier output. We heard a distinctive "click” sound. By slowing the horizontal time period to one second/division, we could see the entire several-millisecond-long noise pulse. But this was no ordinary noise pulse -- it was actually a perfect bipolar square wave.
Envision a single period of a full sine wave on a scope screen, then convert that same wave pattern to fit a bipolar square wave. That's exactly what it was. Every few seconds it appeared, but each time, the starting and ending polarity was flipped. There was no question this was an intelligently generated signal -- but from where?
Soon, a pattern was discernible. Pulse spacing was a consistent 5.5 seconds.
Remember, this laboratory was about 60 feet underground. The building had corrugated steel plates as the base, with three reinforced concrete floors up above. Line of sight with the local radar dish required that you travel through wet dirt, steel, rock, and reinforced concrete for about two miles at a slight upward angle to reach the local airport dish. And microwaves will not travel through any of these materials very well.
Certain types of microwave sources contain a property few engineers know about -- scalar energy. Scalar electromagnetic waves have the E and B fields in phase, unlike normal electromagnetic waves where E and B fields are typically 90 degrees out of phase. There is another interesting characteristic of scalar waves -- they are not stopped by shielding, even by a Faraday cage. When E and B fields are in phase, they do not interact with metal molecules like conventional RF does, which makes shielding useless. Usually, only distance can stop scalar waves. Based on the waveform period, there could be only one source of this signal.
I called the local international airport TRACON group, which stands for TRacking and CONtrol. My one question to the engineer on duty was simply this: "What is the rotation period of your radar dish? I'm certain I'm picking up your signal at the university." He replied: "Let me look out the window and see."
A short time later, he came back to the phone, saying: "About five and a half seconds." Ah Ha! There was my signal source. Conventional microwave theory says this was impossible, but there it was. Clearly these were not conventional microwaves at all. The engineer then asked where I was picking up their signal and I told him. He mumbled, "Guess it would be good for tracking submarines, too."
Apparently, I was correct. This scalar signal disappeared overnight and never returned. As for the real purpose of this scalar pulse, which traveled through two miles of dirt, reinforced concrete, steel, and rock? It remains unknown to this day. Shutting down that short-lived signal, which was transmitted for just one day, did not cause the airport to close. Apparently, it had little to do with air traffic control.
Here is the strangest part of all: It was a signal that was DC-based and detected by a neural amplifier with a -3db bandwidth of 50Hz. No diode detector, no RF amplifier, no demodulators, no IF stages, no dish, no waveguides, none of the usual RF components. Yet, this very low frequency signal definitely originated from a radar dish after traveling through about two miles of dirt and other materials.
This entry was submitted by Ted Twietmeyer and edited by Rob Spiegel.
Ted Twietmeyer’s background includes a patented optical backplane technology. He also has more than 30 years of experience in defense and aerospace systems engineering, project management, and the training of customer technical personnel. Since 2000, Ted has been designing advanced, custom-designed, high-performance systems at the board level.
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