Get ’em while they’re hot: a new session of HackadayU just opened with classes from three fantastic instructors and seats are filling up fast.
Introduction to Antenna Basics — Instructor Karen Rucker teaches the fundamentals of antenna design as if it were your first year on-the-job. She’ll cover the common types of antenna designs and the fundamentals of radio frequency engineering that go into them. Begins Thursday, May 6th.
Raspberry Pi Pico and RP2040 – The Deep Dive — Instructor Uri Shaked guides the class through the internals of the RP2040 microcontroller, covering system architecture, hardware peripherals, and dipping into some ARM assembly language examples. Begins Wednesday, May 5th.
Designing with Complex Geometry — Instructor James McBennett helps you up your 3D modelling game with a course on using complex geometries in Grasshopper3D (part of Rhino3D). Dive into Non-uniform rational B-spline (NURBS) and go from simple shapes to incredibly complex objects with a bit of code. Begins Tuesday, May 4th.
Each course includes five weekly classes beginning in May. Being part of the live class via Zoom offers interactivity with the instructor and other attendees. All tickets are “pay-as-you-wish” with a $20 suggested donation; all proceeds go to socially conscious charities.
For the benefit of all, each class will be edited and published on Hackaday’s YouTube channel once this session has wrapped up. Check out our playlists for past HackadayU courses, or watch them all in one giant playlist.
You might also consider becoming an Engineering Liaison for HackadayU. These volunteers help keep the class humming along for the best experience for students and instructors alike. Liaison applications are now open.
Continue reading “New HackadayU Classes: Antenna Basics, Raspberry Pi Pico, And Designing Complex Geometry”
Watch Justin McAllister’s presentation on simple antennas suitable for a zombie apocalypse and two things will happen: you’ll be reminded that everything antennas do is amazing, and their reputation for being a black magic art will fade dramatically. Justin really knows his stuff; there is no dangle-a-wire-and-hope-for-the-best in his examples. He demonstrates that it’s possible to communicate over remarkable distances with nothing more than an off-the-shelf radio, battery pack, and an antenna of simple design.
Continue reading “Justin McAllister’s Simple, Post-Apocalypse-Friendly Antennas”
The old maxim is that if you pay peanuts, you get a monkey. That’s no longer true, though: devices like the Raspberry Pi W have shown that a $10 device can be remarkably powerful if it is well designed. You might not appreciate how clever this design is sometimes, but this great analysis of the antenna of the Pi W by [Carl Turner, Senior RF Engineer at Laird Technology] might help remind you.
Continue reading “Raspberry Pi W Antenna Analysis Reveals Clever Design”
Radiation patterns for antennas can be utterly confusing, especially when presented in two dimensions, as they usually are. Fear not, [Hunter] has your back with 3D printed and color-coded radiation patterns.
In the field of antenna design, radiation patterns denote the relationship between the relative strength of radio waves emitted from antennas and the position of a receiver/transmitter in 3D space. In practice, probes can be used to transmit/receive from documented locations around an antenna while recording signal intensity, allowing researchers and engineers to determine the characteristics of arcane antennas. These measurements are normally expressed as two-dimensional slices of three-dimensional planes. Naturally, this sometimes (often) complex geometry is difficult for all but the most spatially inclined to mentally conceptualize with only the assistance of a 2D drawing. With computers came 3D models, but [Hunter] wasn’t satisfied with a model on a screen: they wanted something they could hold in their hands.
To that end, [Hunter] simulated several different antenna structures, cleaned up the models for 3D printing, and 3D printed them in color sandstone, and the end result is beautiful. By printing in colored sandstone through Shapeways, [Hunter] now has roughly walnut-sized color-coded radiation patterns they can hold in their hand. To save others the work, [Hunter] has posted his designs on Shapeways at Ye Olde Engineering Shoppe. So far, he has a horn antenna, dipole, inset fed patch antenna and a higher order mode of a patch antenna, all of which are under 15.00USD. Don’t see the antenna radiation pattern of your dreams? Fret not, [Hunter] is looking for requests, so post your ideas down in the comments!
Further, beyond the immediate cool factor, we can see many legitimate uses for [Hunter’s] models, especially in education. With more and more research promoting structural rather than procedural learning, [Hunter’s] designs could easily become a pedagogical mainstay of antenna theory classes in the future. [Hunter] is not the only one making the invisible visible, [Charles] is mapping WiFi signals in three dimensions.
Video after the break.
Continue reading “3D Printed Radiation Patterns”
[Bill Meara] has finished his latest project, a Moxon antenna for HF on 17 meters. [Bill] is well-known here on Hackaday. When not building awesome radios, he can be found ranting about ham radio. His new antenna turned out to be a true hack. He even used a hacksaw to build it!
The Moxon antenna is named for the late [Les Moxon, G6XN] who first described it in “Two-Element Driven Arrays”, a QST magazine article published in July of 1952. [Bill] built his Moxon loosely based on [Jim/AE6AC’s] excellent instructions. The design is incredibly simple – a two element directional antenna using crappie fishing poles as spreaders. That’s crappie as in the fish, not the quality of the pole. Crappie poles are typically made up of telescoping sections of graphite or fiberglass in common lengths of 14, 16, and 20 feet. The poles can be bought for under $20 at sporting goods stores. [Bill] used 16 foot poles purchased from Amazon.
The antenna is created by connecting all four poles at their bases in an X shape. The wire elements are stretched across the ends of the poles. The entire antenna bends up as the stiff poles hold the driven and reflector elements in tension. [Bill] used some scrap wood and U-bolts to attach the fishing poles, and bungee cord ends at the tips. Since the antenna is directional, [Bill] added a TV antenna rotor to spin the beam around. The antenna is so light that one could get by with a couple of cords and the “Armstrong method” of antenna rotation.
Once up on the roof, [Bill] found his antenna really performed. He was easily able to cross the Atlantic from his Northern Virginia home to France, Belgium, and Latvia. The mostly horizontal antenna makes it a bit more unobtrusive than other directional designs. [Bill] mentions that his neighbors haven’t revolted yet, so he’s continuing to enjoy the fruits of his antenna labors.