The Wow! Signal and the Search for Extraterrestrial Intelligence

On a balmy August evening in 1977, an enormous radio telescope in a field in the middle of Ohio sat silently listening to the radio universe. Shortly after 10:00 PM, the Earth’s rotation slewed the telescope through a powerful radio signal whose passage was noted only by the slight change …read more

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Teardown: Cobra XRS 9740 Radar Detector

Drivers with a lead foot more often than not have Waze open on their phone so they can see if other drivers have spotted cops up ahead. But avoiding a speeding ticket used to involve a lot more hardware than software. Back before the smartphone revolution, that same driver would …read more

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Probe the Galaxy on a Shoestring with this DIY Hydrogen-Line Telescope

Foil-lined foam insulation board, scraps of lumber, and a paint-thinner can hardly sound like the tools of a radio astronomer. But when coupled with an SDR, a couple of amplifiers, and a fair amount of trial-and-error tweaking, it’s possible to build your own hydrogen-line radio telescope and use it to …read more

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Umbrella and Tin Cans Turned into WiFi Dish Antenna

There’s something iconic about dish antennas. Chances are it’s the antenna that non-antenna people think about when they picture an antenna. And for many applications, the directionality and gain of a dish can really help reach out and touch someone. So if you’re looking to tap into a distant WiFi network, this umbrella-turned-dish antenna might be just the thing to build.

Stretching the limits of WiFi connections seems to be a focus of [andrew mcneil]’s builds, at least to judge by his YouTube channel. This portable, foldable dish is intended to increase the performance of one of his cantennas, a …read more

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Trio of Magnetrons Power a Microwave Rifle

Can you build a working EM weapon from three microwave ovens? Apparently, yes. Should you do so? Maybe not when the best safety gear you can muster is a metallized Mylar film fetish suit and a Hershey’s Kiss hat.

Proving that language need not be a barrier to perfect understanding of bad ideas, the video below tells you all you need to know, even without subtitles in the non-Russian language of your choice. [KREOSAN]’s build is obnoxiously obvious — three magnetrons mounted on a tin can “resonator” with a foil-covered waveguide at the business end. The magnetrons are tickled by …read more

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