More bedtime reading for super techies only.
Since the ultrasonic microphone has very limited use, and none at all interior to a dwelling, what replaces it? Since you’ve seen lots of spy movies, you know that hidden microphones can be tiny. But they need a connection by wire, or by radio waves. The bug hunter clears a space by scanning for those waves. In the old days, this required time-consuming tuning and listening. The Great Seal Bug operated for years, and was discovered only by accident. But advances in scanning have been matched by advances in bugging.
The wires can be in place for other purposes, carrying the bug’s signal invisibly. The possibilities have multiplied with advances in technology. Nothing is straightforward. Ruses are infinite. Think of every possibility, and you haven’t. Your reasoning cannot be trusted. Harry Caul, a specialist in the trade, was himself bugged, yet unable to find the bug in his own apartment.
Sometimes you just have to demolish the building. (LA Times 1991) Senate OKs $130 Million to Demolish Bug-Riddled U.S. Embassy in Moscow : Appropriations: But with the House calling for ‘top-hatting’ the structure, dispute still is not resolved. The Cuba housing is owned by the Cuban government. What chance is there that it isn’t already wired for hi-fi sound?
So the ultrasonic mike, fingered by CNN “experts” as the source, described by the Google patent, is irrelevant. But ultrasound might be used by a bug in place of radio to transmit what it picks up. (PDF) Recent Developments in Covert Acoustical Communications describes experiments with a Lenovo laptop that suggest this is possible. But by description of the Havana victims, the intensity was orders of magnitude more powerful than required by an information link.
(CNN) Sonic attacks in Cuba hit more diplomats than earlier reported, officials say, offers an important clue. Quoting,
This is very significant. The sound source could not be located. The normal methods and cues of sound localization failed:
- Intensity. Where is it loudest? Walk to it.
- The (pdf) precedence effect.
- The pinnae, the part of the ear hanging on your head, changes the sound as you twist your head, in a way the brain uses to locate the source.
That the sound could not be localized suggests it was generated by a method not found in nature. One such method is mixing of multiple ultrasound frequencies on surfaces inside the room. This is an indication of very high power, because the method is very inefficient.
But occasionally, there is a need to eavesdrop on a room that has not been wired for sound. Might the sneaks then resort to a squealing, brain-damaging ultrasonic mike? It’s actually possible that a device, not the design of Google patents, could be designed to detect the vibrations of a window pane. But the Russians had a much better solution by the late 1930’s, courtesy of Léon Theremin, the Russian who lived in NYC for a while, married a ballerina, and is known for his spooky musical instrument.
It was called the Buran. It used a beam of infrared light, almost invisible to the eye. The beam was projected as a narrow spot onto a window. Some of the light bounced off. The window vibrations caused the spot to jiggle. The jiggles were detected (converted into electricity), amplified, and taped. This simple explanation is not enough for a workable device. There is a dearth of open source.
The modern replacement is the laser mike, for which there is a plethora of detail. Start with a small Maksutov telescope, such as a Questar. Be sure to pick the enhanced silver mirror coating. In place of the eyepiece goes a device about the size of a fist, called an interferometer, which has three more gadgets hanging off it, a laser an attenuator, and a detector. This combo:
- Sends a laser beam to the target
- Receives the bounced beam and makes an exquisitely sensitive comparison, “the difference”, with the original laser beam.
- Sends the difference to a detector.
Depending upon your budget, you can add options like
- Tunable laser.
- Cooled detector.
- De-noising software.
Unlike sound, which is rapidly absorbed by air, light goes much longer distances, miles in clear atmosphere. So if you’re having a tryst in a mountaintop eyrie, you may wish to protect yourself from Harry Caul with Amazon’s Laser Mic Surveillance Defeater Laser Countermeasure Surveillance Protection Device for only $55.99 free shipping.
It’s a buzzer, shaking the window pane. Could it be nulled out? If the subjects of this privacy invasion have left some glasses or plates in view, it might be possible to acquire a reflection, rendering the window-shaker ineffective. Draw the blinds. Are you safe? Don’t bet on it. When there’s a will, there’s a way. I haven’t discussed all the options.
The takeaway: In the open source history of surveillance, there is no recorded occasion of a “bug” making noise, with one exception: the telephone with the noisy line. Those were real, when a “tap” was the attachment of an actual copper wire to a plain old POTS line. No longer.
The takeaway: As the cause the Havana sonic attacks, a malfunctioning bug is completely implausible. If the attacks were not a case of mass hysteria, if they were real, as in causing physical harm, they were intentional.
More bedtime reading later. But first, check under the bed. Then,