Amateur radio is the only hobby that offers its licensed operators the chance to legally design, build, and operate high power radio transceivers connected to unlimited antenna arrays for the purpose of communicating anywhere in the world. The most complicated part of this communication system is the single-sideband (SSB) high frequency (HF) transceiver. In reality, due to the proliferation of low-cost amateur equipment, there only exists a very small group of die-hards who actually design, build from scratch, and operate their own SSB transceivers. I am one of those die-hards, and in this post I will show you how to get started.
Project-based learning, hackathons, and final projects for college courses are fulfilling a demand for hands-on technical learning that had previously fallen by the wayside during the internet/multi-media computer euphoria of the late 90’s. By getting back to building actual hardware yourself, Hackers are influencing the direction of education. In this post we will review some of this progress and seek your input for where we go next.
Batteries flat and no cellphone coverage and you need to communicate hundreds of miles? No problem. [Peter Parker VK3YE] has created a wind-up ham radio transmitter built into a discount store crank-handle flashlight (or torch). No batteries – all power comes from you turning the hand crank. This design was inspired by the ‘Gibson Girl’ emergency beacon transmitter used during Second World War. But what used to be an very large, full body cranking box is now tiny and simple to crank. Let’s take a look at he video and the build details after the break.
I’ve developed or have been involved with a number of imaging technologies, everything from DIY synthetic aperture radar, the MIT thru-wall radar, to the next generation of ultrasound imaging devices. Imagery is cool, but what the end-user often wants is some way by which to get an answer as opposed to viewing a reconstruction. So let’s figure that out.
We’re kicking-off a discussion on how to apply deep learning to more than just beating Jeopardy champions at their own game. We’d like to apply deep learning to hard data, to imagery. Is it possible to get the computer to accurately provide the diagnosis?
I helped to organize a seminar series/discussion panel in New York City on November 13th (you know, for those readers who are closer to New York than to Munich). This discussion panel includes David Ferrucci (the guy who lead the IBM Watson program), MIT Astrophysicist Max Tagmark, and the person who created genetic sequencing on a chip: Jonathan Rothberg. As the vanguard of creativity and enthusiasm in everything technical we’d like the Hackaday community to join the conversation.
Good, workable test gear is key to enabling our hobby. In this post we will discuss where to procure it at rock-bottom prices, what to look for, how to fix it, and how to tailor your laboratory practices around gear that may not be reliable.
We are lucky to be living in an era with plentiful high-quality test gear. Since the Second World War, surplus test gear has been in abundance at low costs enabling hobbyists, innovators, and academics to experiment and build great things. If you are willing to think before you measure you can save serious amounts of money and have a professional laboratory in your home.
Where to buy
The obvious answer is eBay, but the deals on test equipment are at the hamfests. Don’t be fooled by the name. Hamfests sell much more than amateur radio equipment. Hamfests are swap meets where hobbyists trade electronics of all kinds. Check out the ARRL hamfest calendar to find the next local one near you! I suggest you arrive early, however. The culture of hamfests tends to favor showing up as soon as the doors open and leaving about two hours before the official end. The early bird gets the worm!
Before the second world war Radio was a revolution in mass-communication much like the internet today. Fortunes were made and lost, empires built, epic patent battles ensued, all of which resulted in the world being more connected than ever before, which makes for a really great story (and a great Ken Burns documentary).
Last month we showed you how to modify a vintage radio to play your own audio source through it while re-using the existing electronics and maintaining its functionality. In this post we will show you how to restore any vacuum tube radio. You will learn basic repair/restoration procedures from a different era when it was actually worth repairing consumer electronics. Plug into history and get your hands on the most influential technology of the first-half of the 20th century!
Sometimes it is not how good but how bad your equipment reproduces sound. In a previous hackaday post the circuitry of a vintage transistor radio was removed so that a blue tooth audio source could be installed and wired to the speaker. By contrast, this post will show how to use the existing circuitry of a vintage radio for playing your own audio sources while at the same time preserving the radio’s functionality. You will be able to play your music through the radio’s own audio signal chain then toggle back to AM mode and listen to the ball game. Make a statement – adapt and use vintage electronics.
Pre-1950’s recordings sound noisy when played on a high-fidelity system, but not when played through a Pre-War console radio. An old Bing Crosby tune sounds like he is broadcasting directly into your living room with a booming AM voice. You do not hear the higher frequency ‘pops’ and ‘hiss’ that would be reproduced by high-fidelity equipment when playing a vintage recording. This is likely due to the fact that the audio frequency signal chain and speaker of an antique radio are not capable of reproducing higher frequencies. Similarly, Sam Cooke sounds great playing out of an earlier transistor radio. These recordings were meant to be played on radios from the era in which they were recorded.
Choosing an Antique Radio
Vintage radios can be found at garage sales, estate sales, hamfests, antique shops, antique radio swap meets, and Ebay. Millions of radios have been manufactured. People often give them away. For this reason, antique radios are relatively inexpensive and the vast majority are not rare or valuable.
Generally speaking, tube radios must be serviced and may not even work. Transistor radios often work to some level. Try to find a radio that is clean and uses a power supply transformer or batteries.
Click past the break to learn how to restore these radios to working condition