US State Department's surveillance tech exhibit
The US Department of State's Countermeasures Directorate launched a new public exhibition titled ""Listening In: Electronic Eavesdropping in the Cold War Era." Scientific American posted a slideshow of the exhibition and much of the text written about the devices, from old-school keyloggers to phone tap detectors. From SciAm:
IBM SELECTRIC TYPEWRITERSpying on the Spies (SciAm, thanks JR Minkel!), "Listening In: Electronic Eavesdropping in the Cold War Era" PDF brochure (US Dept. of State)
Because the Selectric coupled a motor to a mechanical assembly, pressing different keys caused the motor to draw different amounts of current specific to each key. By closely measuring the current used by the typewriter, it was possible to determine what was being typed on the machine. To prevent such measurements, State Department Selectric typewriters were equipped with parts that masked the messages being typed.
the latest
latest episodes
So cool ...micro-current variations reconstructed into something much bigger...
I used to just slip the underpaid secretaries a hundred and they'd TELL me what they typed.
This reminds me of HeathKit catalogs, issues of "Popular Electronics", and the advertising in the back of old Scientific Americans back in the 70s!
Takuan, I hate to say it but we paid them more to take your money and tell you what we wanted you to know. We have suspicions though that Antonious was however paying them to take our money to take your money and then telling you not what we wanted them to tell you but rather what he wanted them to tell you so we would think we knew but we didn't.
thank goodness I had the back-up bug in the light fixture!
Masking current fluctuations is cool, but the best way to find out what's been typed on a Selectric is to wait until the owner/user steps away for a moment, and swap out its ribbon cartridge. It only takes a few seconds -- Selectrics were a great piece of engineering -- and since no character occluded another on the used ribbon, you could reconstruct every keystroke. Getting the correction ribbon on a correcting Selectric would be nice too, but it's not strictly necessary.
Takuan's got the best suggestion.
The stuff they're willing to reveal today about tactics used in days past makes one wonder what the various spy agencies are up to now...
Scary.
USERW014 @3, Totally. Ah, the good old days. Dale Dougherty, who created MAKE:, was directly inspired by those old Popular Science magazines.
In the 80's I saw a demonstration by an Air Force TEMPEST inspection team that actually used a Selectric III to make this point. One guy typing a letter in one room was recreated in another room with little, if any, error. Amazing!
@Teresa: That's useful for amateur spying, but anyone typing anything remotely sensitive would have been using a Tech III ribbon (ink-based, not carbon, color coded blue, not orange), which does overstrike. Thus the need to get technical.
I love my Selectic II. 15" writing line. Thirty years old, and still typing beautifully.