Collaborate Disseminate
Plasma cutters are ridiculously cheap these days, just cruise by the usual online sources or your local Harbor Freight if you’ve got any doubt about that. But “cheap” and “good” …read more Continue reading Simple Add-On Makes Cheap Plasma Cutter Suitable for CNC Use
HF radios often use toroidal transformers and winding them is a rite of passage for many RF hackers. [David Casler, KE0OG] received a question about how they work and answered …read more Continue reading Toroid Transformers Explained
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
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
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
Joule thief are small, fun circuits which exploit a few characteristics of electronics and LEDs in order to “steal” virtually all of the energy stored in a battery. They can operate at incredibly small voltages and are fairly simple to make. With a few modifications to this basic circuit it’s …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
We generally cast a skeptical eye at projects that claim some kind of superlative. If you go on about the “World’s Smallest” widget, the chances are pretty good that someone will point to a yet smaller version of the same thing. But in the case of what’s touted as “The …read more
Continue reading Camcorder Viewfinder Converted to Diminutive Vector Display
Finding just the right off-the-shelf part to complete a project is a satisfying experience – buy it, bolt it on, get on with business. Things don’t always work out so easily, though, which often requires the even more satisfying experience of modifying an existing part to do the job. Modifying a stepper motor by drilling a hole down its shaft probably qualifies for the satisfying mod of the year award.
That’s what [Russ] did to make needed improvements to his CNC flat-coil winder, which uses a modified delta-style 3D-printer to roll fine magnet wire out onto adhesive paper to form …read more
Continue reading Stepper Motor Mods Improve CNC Flat Coil Winder