4 ms·
One way you can do this without another light source is to bounce a laser beam off a window or other things that are reflective. In fact, the same principle ca
by ravenstine 6y ago
One way you can do this without another light source is to bounce a laser beam off a window or other things that are reflective.
In fact, the same principle can be achieved with radio. The Russians once planted a device in a wooden seal they gave to a US ambassador as a gift which, when a focused radio beam was aimed at it, would reflect and oscillate that beam due to vibrations in the air.
https://en.wikipedia.org/wiki/The_Thing_%28listening_device%29 https://en.wikipedia.org/wiki/The_Thing_%28listening_device%...
- perch56 6y agoLeon Theremin was a genius that also created one of the first electronic instruments carrying his name now. https://en.wikipedia.org/wiki/Theremin https://en.wikipedia.org/wiki/Theremin
- russellbeattie 6y agoI remember in the 1990s I was doing contracting work in SoCal and got a job at one of the big defense contractors near LAX. (Trying to remember which one... Hughes?) I lasted only one week as the building was totally secure - no windows at all. Life is waaaaaay to short to work in a hole like that. Maybe someone with more info can fill in the details, but if I remember correctly, when Nokia changed their Silicon Valley offices to downtown Sunnyvale almost a decade ago, they were worried because Apple had offices in the adjacent building. If I remember correctly Nokia put in a bunch of security glass to prevent spying from vibrations in the windows. (There's some irony there, I know...)
- panda88888 6y agoYup. It's fairly standard. For classified work the rooms and entry/exit protocols have to meet certain security requirements based on the classification level. No windows and no electronics are standard. No walls that is exposed to the exterior. I've been in room within a room setup when it was warranted.
- acidburnNSA 6y agoBack in the 90's I found an old cardboard box full of radioshack electronics components and a paper schematic of how to put it together. I asked my dad what it was. He had been into an electronics hobby in the 1980s and told me that it was a amplifier to receiving laser light bounced off of a window for spy stuff. I couldn't believe it. The kit became my first significant soldering project. I got it all together and put my beloved laser pointer on a tripod and tried bouncing it in. I never did get it to the point that I could hear voices but boy could I ever hear cool vibration noises when I tapped the window. It was extremely fun and I've been soldering things here and there ever since.
- Darkphibre 6y agoJust a thought: Could be your window was doublepane for insulation? The airgap would probably act as a buffer. Regardless, awesome story. I'm glad you found an engineering passion, and kudos to your dad for letting you run with it! :)
- acidburnNSA 6y agoThanks! It was a double-pane sliding glass door actually so maybe that did have something to do with it. Though, I also tried from the same side as the laser for most of my trials (i.e. laser and voice both coming from the inside).
- balls187 6y agoMost of my office windows at Boeing had little ultrasonic buzzers on them to prevent such an attack. On my offices was actually in a large farad cage to reduce/eliminate EMF leaks from workstations.
- acidburnNSA 6y agoWow. That's super interesting. So it was considered a credible threat. Huh you can actually buy such things on Amazon. https://www.amazon.com/Shomer-Tec-SHLSD-Laser-Surveillance-Defeater/dp/B00ABV7J0C https://www.amazon.com/Shomer-Tec-SHLSD-Laser-Surveillance-D... Edit: yikes, those reviews...
- spitfire 6y agoWoah. Check out the recommendations on that page. There's some great stuff in there.
- ravenstine 6y agoIt's basically a 555 timer, some resisters, and a piezo buzzer. Hardly worth 50 bucks! You can build one yourself for a mere fraction of that.
- freehunter 6y agoFor a big business like Boeing, buying one at $50 would be far more palatable than building one from parts.
- ravenstine 6y agoDang, you're right! This is a business I need to get into.
- zszugyi 6y agoI'm sure getting vetted to be a vendor for DoD/Government projects is super easy.
- mhh__ 6y agoIn any building spies had access to there was a game of cat and mouse as (for example) spies would see people with radio equipment scouring rooms through the window as they heard their bugs go pop one by one. Peter Wright (who wrote spycatcher) was the one who first got to look at The Thing; He actually broke it and had to make a new membrane for the microphone. He also invented (within MI5 at least) their technique for detecting superhet receivers (RAFTER), at one point they apparently were parked next to the soviet receiver.