Category: Hackaday

via HACKADAY: Restoring A 1930s Oscilloscope – Without Supplying Power

We’ve all done it: after happening across a vintage piece of equipment and bounding to the test bench, eager to see if it works, it gets plugged in, the power switch flipped, but… nothing. [Mr Carlson] explains why this is such a bad idea, and accompanies it with more key knowledge for a successful restoration […]

via HACKADAY: This Mostly 3D-Printed Discone Antenna Is Ready For Broadband Duty

For hams and other radio enthusiasts, the best part of the hobby is often designing antennas. Part black magic, part hard science, and part engineering, antenna design is an art. And while the expression of that art often ends up boiling down to pieces of wire cut to the correct length, some antennas have a […]

via HACKADAY: How Hertha Aryton Enabled the Titanic to Call SOS

[Kathy] recently posted an interesting video about the connection of an electronics pioneer named [Hertha Ayrton] to the arc transmitter. The story starts with the observation of the arc lamp — which we learned was a typo of arch lamp. [Hertha] was born into poverty, but — very odd for the day — obtained a science education. […]

via HACKADAY: Disaster Area Communications With Cloud Gateways

2017, in case you don’t remember, was a terrible year for the Caribbean and Gulf coast. Hurricane Maria tore Puerto Rico apart, Harvey flooded Houston, Irma destroyed the Florida Keys, and we still haven’t heard anything from Saint Martin. There is, obviously, a problem to be solved here, and that problem is communications. Amateur radio only […]

via HACKADAY: Tiny Transmitter Brings Out the Spy Inside You

When it comes to surveillance, why let the government have all the fun? This tiny spy transmitter is just the thing you need to jumpstart your recreational espionage efforts. We kid, of course — you’ll want to stay within the law of the land if you choose to build [TomTechTod]’s diminutive transmitter. Barely bigger than the 337 button […]

via HACKADAY: Temperature Sensor and Simple Oscillator Make a Value-Added HF Beacon

Sometimes the best projects are the simple, quick hits. Easily designed, fast to build, and bonus points for working right the first time. Such projects very often lead to bigger and better things, which appears to be where this low-power temperature beacon is heading. In the world of ham radio, beacon stations are transmitters that generally operate […]

via HACKADAY: 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 antennamight be just the […]

via HACKADAY: An FM Transceiver From An Unexpected Chip

The Si47xx series of integrated circuits from Silicon Labs is a fascinating series of consumer broadcast radio products, chips that apply SDR technologies to deliver a range of functions that were once significantly more complex, with minimal external components and RF design trickery.  [Kodera2t] was attracted to one of them, the Si4720, which boasts the […]

via HACKADAY: eTextile Spring Break Tackles Signal Blocking, Audio Generation, and Radio Transmissions

Finding a killer application for e-textiles is the realm of the hacker and within that realm, anything goes. Whether it’s protecting your digital privacy with signal shielding, generating audio with a wearable BeagleBone or 555 timer, or making your favorite garment into an antenna, the eTextile Spring Break is testing out ways to combine electronics […]

via HACKADAY: SDR IF Experiments

The R820T tuner IC is used in the popular Airspy software defined radio (SDR) as well as many of the inexpensive RTL SDR dongles. [TLeconte] did some experiments on intermediate frequency (IF) configuration of the chip, and you’ll find his results interesting. Using 5 million samples per second and the device’s real mode, the tests look at […]

via HACKADAY: Beeping The Enemy Into Submission

In July 1940 the German airforce began bombing Britain. This was met with polite disagreement on the British side — and with high technology, ingenuity, and improvisation. The defeat of the Germans is associated with anti-aircraft guns and fighter planes, but a significant amount of potential damage had been averted by the use of radio. […]

via HACKADAY: Another Reason to Learn Morse Code: Kidnapping

Morse code — that series of dots and dashes — can be useful in the strangest situations. As a kid I remember an original Star Trek episode where an injured [Christopher Pike] could only blink a light once for yes and twice for no. Even as a kid, I remember thinking, “Too bad they didn’t think […]

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