Printing Magnets
A research center in Spain has been working on ways to solve recent supply chain issues. One of these issues is a shortage of materials to make magnets. Their answer? …read more Continue reading Printing Magnets
Collaborate Disseminate
A research center in Spain has been working on ways to solve recent supply chain issues. One of these issues is a shortage of materials to make magnets. Their answer? …read more Continue reading Printing Magnets
Looking to get into fault injection for your reverse engineering projects, but don’t have the cash to lay out for the necessary hardware? Fear not, for the tools to glitch …read more Continue reading Blast Chips with This BBQ Lighter Fault Injection Tool
Amateur Radio as a hobby has a long history of encouraging experimentation using whatever one might have on hand. When [Tom Essenpreis] wanted to use his 14 MHz antenna outside …read more Continue reading Surplus Syringes Make Satisfactory Tuner for Amateur Radio Experimentation
So far in the $50 Ham series, I’ve concentrated mainly on the VHF and UHF bands. The reason for this has to do mainly with FCC rules, which largely restrict Technician-level licensees to those bands. But there’s a financial component …read more
Continue reading The $50 Ham: A Cheap Antenna for the HF Bands
Amateur radio operators and shortwave listeners have a common enemy: QRM, which is ham-speak for radio frequency interference caused by man-made sources. Indiscriminate, often broadband in nature, and annoying as hell, QRM spews forth from all kinds of sources, and can be difficult to locate and fix.
But [Emilio Ruiz], …read more
Continue reading Tracking Down Radio Frequency Noise Source, With Help from Mother Nature
Let’s say you’re stranded on a desert island and want to get the news from the outside world. You’ll have to build your own crystal radio, of course, but your parts bin is nowhere to be found and Digi-Key isn’t delivering. So you’ll need to MacGuyver some components. Capacitors are …read more
Continue reading Digging in the Dirt Yields Homebrew Inductors
Anyone who has ever wound a toroidal coil by hand can tell you that it’s not exactly a fun job. Even with the kinds of coils used in chokes and transformers for ham radio, which generally have relatively few windings, passing all that wire through the toroid time after time …read more
Continue reading Homebrew Coil Winder Makes Toroids a Snap to Wind
Radio frequency electronics can seem like a black art even to those who intentionally delve into the field. But woe betide the poor soul who only incidentally has to deal with it, such as when seeking to minimize electromagnetic interference. This primer on how RF chokes work to reduce EMI …read more
Next time you get a new device and excitedly unwrap its little poly-wrapped power supply, remember this: for every switch-mode power supply you plug in, an amateur radio operator sheds a tear. A noisy, broadband, harmonic-laden tear.
The degree to which this fact disturbs you very much depends upon which …read more
Continue reading The RFI Hunter: Looking for Noise in All the Wrong Places
A fully stocked freezer can be a blessing, but it’s also a disaster waiting to happen. Depending on your tastes, there could be hundreds of dollars worth of food in there, and the only thing between it and the landfill is an uninterrupted supply of electricity. Keep the freezer in an out-of-the-way spot and your food is at even greater risk.
Mitigating that risk is the job of this junkbox power failure alarm. [Derek]’s freezer is in the garage, where GFCI outlets are mandated by code. We’ve covered circuit protection before, including GFCIs, and while they can save a life, …read more