Readers of a certain age will remember the payphone trick of letting the phone ring once and then hanging up to get your quarter back. This technique was used with a pre-planned call time to let someone know you made it or you were okay without accruing the cost of a telephone call. As long as nobody answered you didn’t have to pay for the call, and that continues to be the case with some pay-per-minute cellphone plans.
This is the concept behind [Antonio Ospite’s] ringtone data transfer project called SaveMySugar. Don’t judge him, this work has been ongoing for around ten years and started back when cellphone minutes were a concern. We’re just excited to see that he got the excruciatingly slow thing to work.
Those wanting to dig down to the nitty-gritty of the protocol (and you should be one of them) will want to read through the main project page. The system works by dialing the cellphone, letting it ring once, then hanging up. The time between redials determines a Morse code dot, dash, or separation between characters. Because you can’t precisely determine how long it will take each connection to read, [Antonio] built ‘noise’ measurement into the system to normalize variations. The resulting data transfer works quite well. He was able to transfer the word “CODEX” in just six minutes and thirty seconds. But it is automatic, so what do you care? See the edge-of-your-seat-action play out in the video below.
If you can’t stomach that baud, here’s a faster Morse code data transmitter but it doesn’t use the phone.
Continue reading “Free Cell Data Transfer with Slowest Morse Code Ever”
Helping hands are a common soldering aid. These inexpensive devices usually have a substantial base, a pair of alligator clips to hold a workpiece, and sometimes a magnifying glass. [Yonatan24] (who happens to be 13 years old) built his own set using a siren horn as a base. Lately, however, he decided to enhance it quite a bit to use Gorillapod arms and incorporate a solder cleaning and a variety of other features. Of course, there is a magnifier along with a solder waste collection bin.
The build is well-detailed, although since [Yonatan24] salvaged some of the parts, you might have to make adjustments to match the parts you use. The Gorillapod arms are from a cheap tripod, but a lot of the material was left over or stripped from junk (like the lead weight).
We’ve seen workbench PCB holders before (including a 3D printed one), of course, but you have to admire the look of this one, as well as the overboard set of features.
[cpldcpu] just can’t leave the mysteries of candles alone. We’ve covered his explorations of candle flicker LEDs before, but this time he’s set his sensors on the real thing. [cpldcpu] hooked a photodiode to his oscilloscope, pointed it at a candle flame, and recorded the result.
The first interesting observation was the candle slowly changed brightness, whether it was interacted with or not. Next he measured the effect when the flame was disturbed by small gusts of air. This produced a bright flicker with an oscillation at 5Hz before returning to steady state, which as [stygiansonic] mentioned in a the Hacker News comment, is a known phenomenon used in flame detectors. Neat! There’s even an equation:
Under normal gravity conditions, the flames have a well defined oscillation frequency which is inversely proportional to the square root of the burner diameter, D, and to a good approximation can be written as f » 1.5/D½, with D given in meters.
[cpldcpu] then compiled his measurements into a series of graphs and ultimately an animated gif comparing the candle steady state, a real candle’s flicker, and the flicker he recorded from a candle flickr LED. It’s surprising how different the fake is from the real thing. You can look at his measurements and code at his github.
[via Hacker News]
One of the redeeming qualities of many modern cheap keyboards is the built-in volume control buttons. But this is Hackaday, and many of us (and you) have Model Ms or newfangled mechanical keyboards that only have the essential keys. Those multimedia buttons only adjust the system volume anyway. We would bet that a lot of our readers have sweet sound systems as part of their rig but have to get up to change the volume. So, what’s the solution? Build a color-changing remote USB volume knob like [Markus] did.
Much like the Instructable that inspired him, [Markus] used a Digispark board and a rotary encoder. The color comes from a WS2812 LED ring that fits perfectly inside a milky plastic tub that once held some kind of cream. When the volume is adjusted, the ring flashes white at each increment and then slowly returns to whatever color it’s set to. Pushing the button mutes the volume.
The components are pretty lightweight, and [Markus] didn’t want the thing sliding all over the desk. He took an interesting approach here and filled the base with the lead from a shotgun round and some superglue. The rotating part of the button needed some weight too, so he added a couple of washers for a satisfying feel. Be sure to check out the demonstration after the break.
Digispark board not metal enough for you? Here’s a volume knob built around a bare ATtiny85 (which is the same thing anyway).
Continue reading “Pump Up the Volume with Lead Shot and LEDs”
The Internet is polluted with craziness, and there is no better example than YouTube. If you’ve ever wondered what would happen when you give everyone on the planet the power to show everyone else on the planet their innermost thoughts, desires, and insane ramblings, you need only look at YouTube.
One of the biggest offenders of incoherent ramblings is the subject of spaceflight. Simply search ‘space shuttle’ on YouTube, and you’ll find accusations of the crew of Columbia being abducted by aliens. Crazy, incoherent, and somewhat insulting. Accusations of a moon landing conspiracy are unavoidable in the ‘related videos’ section and are similarly filled with videos from people with either a tenuous grasp of reality or too much time on their hands.
A broken clock is right twice a day, a broken calendar is right every twenty-eight years or so, and every once in a while, simply from the volume of videos on the subject, one conspiracy theorist will present a new and novel idea. Here we present perhaps the only moon landing conspiracy theory that makes sense, is consistent with physical laws, and that may actually be true.
Continue reading “The Most Plausible Apollo Moon Landing Conspiracy Ever Devised”
CES, the Consumer Electronics Show, is in full swing. That means the Hackaday tip line is filled to the brim with uninteresting press releases, and notices that companies from the world over will be at CES.
3D printing has fallen off the radar of people who worship shiny new gadgets of late, and this is simply a function of 3D printing falling into the trough of disillusionment. The hype train of 3D printing is stuck on a siding, people are bored, but this is the time that will shape what 3D printing will become for the next ten years. What fascinating news from the 3D printing industry comes to us from CES?
Continue reading “The 3D Printers of CES”
There is a fascinating brain reaction known as the McCollough Effect which is like side-loading malicious code through your eyeballs. Although this looks and smells like an optical illusion, the science would argue otherwise. What Celeste McCollough observed in 1965 can be described as a contingent aftereffect although we refer to this as “The McCollough Effect” due to McCollough being the first to recognize this phenomena. It’s something that can’t be unseen… sometimes affecting your vision for months!
I am not suggesting that you experience the McCollough Effect yourself. We’ll look at the phenomena of the McCollough Effect, and it can be understood without subjecting yourself to it. If you must experience the McCollough Effect you do so at your own risk (here it is presented as a video). But read on to understand what is happening before you take the plunge.
Continue reading “Hack Your Brain: the McCollough Effect”