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Post by hua man on May 28, 2018 20:39:25 GMT -6
Does anyone remember Black Sound or Black Noise? Basically, it's a sonic frequency that can induce heart attacks without proper hearing protection. I read about it in the mid-80s, so tech manipulation today could grade it to a gray noise causing nausea and dizziness. Any Old School Cold War theories sound similar to this?
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Post by papaof2 on May 30, 2018 11:05:33 GMT -6
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Post by willc453 on Dec 6, 2020 12:04:24 GMT -6
Remember our diplomatic people overseas getting sick a few years ago? Read an article within the last week where it's figured microwaves did this....and it wasn't ours. Also, several years ago, the Army was testing a new weapon using some sort of radar on people as a form of crowd control, possible battlefield use. It would make you feel from being uncomfortable to feeling like you were on fire, with the effects quickly gone within a minute or two of the machine being turned off. Haven't seen any further news on it any more than I have on the Air Force testing EMP missiles.
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Post by papaof2 on Dec 6, 2020 12:34:08 GMT -6
In the late 50's and into the 60's/70's, they found that high frequency sound just above hearing range (over 20kHz) made people feel bad. As hi-fi got to be higher-fi, people experimented to see what they could hear above 15kHz.
Ultrasonic-capable tweeters are very directional devices so you could have a focused beam of "bad" sound. A London shopkeeper had them in front of his business to drive the loiters away when needed - at least until he was found out.
With the small size of some current tweeters, you could now have a pattern of them and small LED floodlights and the tweeters would just look like LED's that needed to be replaced.
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Post by papaof2 on Nov 3, 2023 5:37:29 GMT -6
Pair of 300 watt RMS tweeters for $60 - advertised response up to 20,000Hz but actual response probably well above that to have nearly flat response from 3,500Hz to 20,000Hz. You just need the amplifier than can provide 300 watts/channel to your pair of tactical tweeters and a source of 22,000 to 30,000Hz - Banggood or AliExpress has a kit for under $30. www.amazon.com/Timpano-TPT-ST25-Sensitivity-Tweeters-Speakers/dp/B0C2XZFZ3TNo, Agent Smith, I'm not building an audio weapon. These are for the audio system in my jumping car.
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Post by gipsy on Nov 3, 2023 9:01:07 GMT -6
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Post by papaof2 on Nov 3, 2023 10:26:00 GMT -6
If I built an audio weapon, I'd want a BIG drone to carry it and its power amp and batteries. Probably need at least 30 minutes of flight time when carrying maybe a 20 - 30lb load for it to be really useful. Definitely need some auto-pilot capability to help with level flight and a one meter GPS to get it to its destination and back to its starting point. Think how simple it would be to quiet the drunks partying two houses down on the other side of the road - program the drone to leave your backyard, go 300 feet down the road, cross over the road and get above backyards there and then hover over the target group, turn up the volume and slowly drop to 15 feet above the ground - the 4K camera would allow you to directly target troublemaker(s) in the group. Just have FEMA or BATFE or DEA in flashing blue lights on the side of the drone.
That sounds like something Jack Wilson might build ;-)
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Post by feralferret on Nov 5, 2023 21:58:23 GMT -6
Look up "Havana Syndrome".
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Post by papaof2 on Nov 5, 2023 22:40:08 GMT -6
That also happened in the late '60's or '70's. Enough that Popular Electronics' "Carl and Jerry" series had a story about it. I'll see if I can find that story tucked away somewhere in the 2TB drive on this laptop. That series was published in (I think) 3 volumes in 2007 or so. There's and archive of Popular Electronics articles here: www.rfcafe.com/references/popular-electronics/vintage-popular-electronics-magazine-articles.htmThe one on "Silent Sound" is a general coverage of ultrasonic sounds - don't remember if it covers using it as a weapon and that's from 1958. There's "a steam powered ham rig", among other things. Multiple publications of electronics/technology comics. 59 "Carl and Jerry" references so I won't get all of those read any time soon :-(
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Post by papaof2 on Nov 5, 2023 22:41:57 GMT -6
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Post by feralferret on Nov 6, 2023 0:55:16 GMT -6
I see that the archive also includes the "Electronics Experimenters Handbook" issues. I used to have several of those with plans for some projects i wanted to build. I will have to look through those for sure.
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