1) They're getting effectively nothing above 400Hz. Male speech is 450-650 Hz fundamental and female speech is typically 500-800 Hz fundamental. 2) Their limiting factor is the resolution of the lens, not the resolution of the camera, which is why they've got an extreme telephoto pointed at their bag'o'chips even though it's 6 feet away. The technique is simply not applicable from any kind of useful distance for surveillance. 3) This shit works much better in microwave. Leon Theremin (yes, that theremin) developed a bug for the KGB that had the passive membrane built into a "Great Seal of the United States" (which the US ambassador dutifully hung over his desk). When the KGB beamed microwaves at it, vibration of the membrane altered the capacitance of the dipole circuit, modulating speech over the carrier and allowing the KGB to monitor and record conversations within the embassy from across the street, through walls and everything. That was in 1945. (the cavity opening was the eagle's mouth - droll, no?) Espionage has used laser interferometry to detect vibrations on panes of glass for decades. Thermal glass makes it a lot harder... but a polarizing filter and other trickery gives you much more useful results than camming a bag of chips with your iPhone.
Yeah, you are so right. The Russian Great Seal story is something else. I love this heading: Q. What does "Good Vibrations" by The Beach Boys have in common with the Great Seal's bad vibrations? Back in May 1966, Esquire Magazine was all about "Bugging the Bedroom", Esquire Magazine, May 1966
Wow. That's an amazing article. Did you find that in the link I had above? I'll be honest, I didn't read what I posted; I know about "the thing" from Robert Wallace's book Spycraft which didn't have any pictures, as I did it as an audiobook. Fun fact: the article you linked was written by Nick Pileggi, author and screenwriter of Goodfellas, Casino, City Hall and American Gangster and, from 1987 until her death in 2012, Mr. Nora Ephron.
I liked the martini olive microphone: The link to the Esquire article was in an email discussion ensuing from the MIT article in a mailing list that I happen to be on. ʞɐıuzoʍ ǝʌǝʇs is on this mailing list as well... Anything good that I post usually comes from that crowd.The martini-olive microphone with transmitter has attracted a good deal of attention in the press, was mentioned in a Senate hearing on bugging devices and is de rigueur in spy films. The mike is at the left end of the olive, where the hole should be, and the aerial is concealed inside the toothpick. Actually, this is too expensive ($200), too low-powered and gimmicky for a real pro. Its range is not more than fifty feet, and an operative would need his receiver and tape in the next room. Nevertheless, smart hostesses dispense twists of lemon.
