Misc Hacks

4085 Articles

Binary Calculator For All 0b10 Types

November 10, 2020 by 15 Comments

You know the old joke: There are 10 types of people in the world — those who understand binary, and those who don’t. Most of us on Hackaday are firmly in the former camp, which is why projects like this circuit sculpture binary calculator really tickle our fancies.

Inspired by the brass framework and floating component builds of [Mohit Bhoite], [dennis1a4] decided to take the plunge into circuit sculpture in an appropriately nerdy way. He wisely decided on a starter build, which was a simple 555 timer circuit, before diving into the calculator. Based on an ATMega328P in a 28-pin DIP, the calculator is built on an interesting hybrid platform of brass wire and CNC-routed wood. The combination of materials looks great, and we especially love the wooden keycaps on the six switches that make up the keyboard. There’s also some nice work involved in adapting the TLC5928 driver to the display of 16 discrete LEDs; suspended as it is by fine magnet wires, the SSOP chip looks a bit like a bug trapped in a spider web.

Hats off to [dennis1a4] for a great entry into our soon-to-conclude Circuit Sculpture Contest. The entry deadline is (today!) November 10, so it might be a bit too late for this year. But rest assured we’ll be doing this again, so take a look at all this year’s entries and start thinking about your next circuit sculpture build.

Continue reading “Binary Calculator For All 0b10 Types” →

Infinity Mirror Guitar Shreds Forever

November 9, 2020 by 5 Comments

Just when we thought there was nothing left to make into an infinity mirror, [Burls Art] goes and builds something that seems obvious now that it exists — an infinity mirror guitar. Check out the build video after the break, where [Burls Art] gets right to it without wasting any time.

He started by making a 3/4″ wood frame for the body and the one-piece neck and headstock. The acrylic on the top has two-way mirror film, and the back piece is painted with mirror paint to get the infinity effect going. [Burls Art] also fashioned acrylic boxes for the pickup and the electronics. Those are both buffed to be frosty, so the lights reflect nicely off of them.

There’s nothing super-fancy going on with the electronics, just some app-controlled RGB LEDs. We would love to see a version where the LEDs respond in real time to the music. The effect is still quite cool, so if you don’t want to watch the whole build, at least check out the demo at the end where [Burls Art] plays a riff. Never has a delay pedal been so appropriate.

If you’re not much of a luthier, don’t fret about not being able to make a cover version. We’ve seen plenty of infinity mirrors, but if you want something useful, whip up some infinity drink coasters.

Continue reading “Infinity Mirror Guitar Shreds Forever” →

“Hey, You Left The Peanut Out Of My Peanut M&Ms!”

November 8, 2020 by 20 Comments

Candy-sorting robots are in plentiful supplies on these pages, and with good reason — they’re a great test of the complete suite of hacker tools, from electronics to machine vision to mechatronics. So we see lots of sorters for Skittles, jelly beans, and occasionally even Reese’s Pieces, but it always seems that the M&M sorters are the most popular.

This M&M sorter has a twist, though — it finds the elusive and coveted peanutless candies lurking in most bags of Peanut M&Ms. To be honest, we’d never run into this manufacturing defect before; being chiefly devoted to the plain old original M&Ms, perhaps our sample size has just been too small. Regardless, [Harrison McIntyre] knows they’re there and wants them all to himself, hence his impressive build.

To detect the squib confections, he built a tiny 3D-scanner from a line laser, a turntable, and a Raspberry Pi camera. After scanning the surface to yields its volume, a servo sweeps the candy onto a scale, allowing the density to be calculated. Peanut-free candies will be somewhat denser than their leguminous counterparts, allowing another servo to move the candy to the proper exit chute. The video below shows you all the details, and more than you ever wanted to know about the population statistics of Peanut M&Ms.

We think this is pretty slick, and a nice departure from the sorters that primarily rely on color to sort candies. Of course, we still love those too — take your pick of quick and easy, compact and sleek, or a model of industrial design.

Continue reading ““Hey, You Left The Peanut Out Of My Peanut M&Ms!”” →

Robust Water-Rocket Launcher Gets The Engineering Just Right

November 5, 2020 by 7 Comments

Normally when we run across a project that claims to be overengineered, we admit that we get a little excited. Such projects always hold the potential for entertainingly over-the-top designs, materials, and methods. In this case, though, we’ll respectfully disagree with [Zach Hipps] assessment of his remote-controlled soda bottle rocket launcher as “overengineered”. To us, it seems just right.

That’s not to take away from anything accomplished with this build. Indeed, we’re mighty impressed by the completeness of the build, which was intended to create a station for charging and launching air-powered water rockets. The process started with a prototype, built mainly from 3D-printed parts but with a fair selection of workshop scraps to hold it together. This allowed [Zach] to test the geometry of the parts, operation of the mechanism, and how it interfaced with the flange on the necks of 2-liter soda bottles.

Honestly, the prototype was pretty good by itself and is probably where many of us would have stopped, but [Zach] kept going. He turned most of the printed parts into machined aluminum and Delrin, making for a very robust pneumatically operated stand. We’ve got to say the force with which the jaws close around the bottle flange is a bit scary — looks like it could easily clip off a wayward finger. But if he manages to avoid that fate, such a hearty rig should keep [Zach] flying for a long time. Perhaps it could even launch a two-stage water rocket?

Continue reading “Robust Water-Rocket Launcher Gets The Engineering Just Right” →

Make Some Noise Or Simulate It, At Least

November 3, 2020 by 6 Comments

Noise is a fact of life, especially in electronic circuits. But on our paper schematics and just as often our simulations, there is no noise. If you are blinking an LED on a breadboard, you probably don’t care. But if you are working on something meatier, handling electrical noise gracefully is important and simulation can help you. [Ignacio de Mendizábal] has a great piece on simulating EMC filters using LTSpice that can get you started.

There are many ways of classifying noise and [Ignacio] starts with common-mode versus differential noise, where common-mode is noise with current flowing in the same direction without regard to the circuit’s normal operation, and differential noise having currents that flow in the opposite direction of normal current flow.

Continue reading “Make Some Noise Or Simulate It, At Least” →

Building A Top-Notch Electret Microphone

November 2, 2020 by 25 Comments

Electret microphones are capable of high-quality output, and are prized for their smooth frequency response. However, unlike other types, they can’t simply be plugged directly into a mixing desk. Instead, they require special high-impedence circuitry to extract the audio signal for recording. [DJJules] is a big fan of these microphones, and decided to build a high-quality, easy to use circuit that he has shared with the community. 

The goal of the project was to create a circuit to match the TSB2555B electret capsule that could be used with phantom power, and that could be built with easily obtainable parts. [DJJules] had used FETs in the past, but grew tired of routinely having to hunt for obsolete parts. Instead, this design relies on a dual OPA1642 op-amp, with its low quiescent current meaning it’s perfect for running off phantom power. This means the microphone needs no batteries, and using a dual op-amp enables the circuit to properly drive a balanced audio connection.

The circuit is designed to fit inside a common BM700 or BM800 microphone body, and the PCB can be ordered from PCBWay for those interested in building their own. There’s also a saddle on Shapeways that’s designed to neatly mount the electret capsule within the housing.

The final results are impressive, and this project would make a great entry into the DIY microphone space for anyone eager to start building their own gear. Of course, there are simpler builds if you’re looking for an easier way to get started. Video after the break.

Continue reading “Building A Top-Notch Electret Microphone” →

How Many Punches Does It Take?

November 2, 2020 by 3 Comments

Do you ever wonder just how many punches you have thrown? The answer is going to be different if you happen to use a punching bag as part of your exercise routine. So is the case with the [DuctTapeMechanic] and while restoring an old speed ball punching bag, he decided to combine his passions for sports and electronics by adding a punch counter.

Perhaps most interesting in this build is the method used to monitor the bag. A capacitance proximity sensor most often used for industrial automation is mounted in the wooden base. He just calls it “an NPN capacitive sensor” without mentioning part number but these are rather easy to find from the usual places. It has no problem sensing each punch — assuming you swing strong enough so that the bag comes near the sensor. Two battery packs, an Arduino, and an optocoupler round out the bill of materials. We were a little disappointed not to see any duct tape in the construction of this project, but since the electronics are outside and exposed to the elements, maybe duct tape will be used to install a roof in a future episode.

The [DuctTapeMechanic] likes to repurpose items which would otherwise be thrown away, which is something to be applauded. The frame of this punching bag was welded from a discarded metal bed frame (a regular occupant of crawl spaces and self storage places), and you might remember he repurposed the electric motor from a discarded clothes dryer last month, changing it into a disk sander.

Continue reading “How Many Punches Does It Take?” →