Of course, there’s nothing unusual about using 7-segment displays, especially in a clock. However, [Edison Science Corner] didn’t buy displays. Instead, he fabricated them from a PCB using 0805 LEDs for the segments. You can see the resulting clock project in the video below.
While the idea is good, we might have been tempted to use a pair of LEDs for each segment or used a diffuser to blur the LEDs. The bare look is nice, but it can make reading some numerals slightly confusing.
Integrated circuits, chipsets, memory modules, and all kinds of other transistor-based technology continues to get smaller, cheaper, and more energy efficient as time moves on. Not only are the components themselves smaller, but their supporting infrastructure is as well. Computers like the Raspberry Pi are about the size of a credit card and have computing power on the order of full-sized PCs from a few decades ago. The Arduino is no exception to this trend, either, and this new dev board called the Epi 32U4 might be the smallest ATmega platform we’ve seen so far.
As the name suggests, the board is based around the ATmega32U4 which is somewhat unique among Atmel chips in that it includes support for USB within the chip itself rather than relying on external translating circuitry. This makes it an excellent choice for any project which involves sending keyboard, mouse, or other peripheral information to a computer. This goes a few steps further with eliminating “bloat” compared to other boards, too — there’s no on-board voltage regulator, and just a single LEDs on pin 13.
One of the other features this board boasts over other small form factor boards is on-board USB-C, which is definitely a perk as more and more devices switch away from the various forms of older USB-type plugs. The project’s specifications are also available on this GitHub page for anyone that wants to produce their own. And, if you don’t have a 32U4 on hand and still want to build a keyboard project, it’s possible to get some other Arduinos to support these features but it’ll take a little more work.
Thanks to [Rasmus L] for the tip!
Jenny did an Ask Hackaday article earlier this month, all about the quest for a cheap computer-based audio mixer. The first attempt didn’t go so well, with a problem that many of us are familiar with: Linux applications really doesn’t like using multiple audio devices at the same time. Jenny ran into this issue, and didn’t come across a way to merge the soundcards in a single application.
I’ve fought this problem for a while, probably 10 years now. My first collision with this was an attempt to record a piano with three mics, using a couple different USB pre-amps. And of course, just like Jenny, I was quickly frustrated by the problem that my recording software would only see one interface at a time. The easy solution is to buy an interface with more channels. The Tascam US-4x4HR is a great four channel input/output audio interface, and the Behringer U-PHORIA line goes all the way up to eight mic pre-amps, expandable to 16 with a second DAC that can send audio over ADAT. But those are semi-pro interfaces, with price tags to match.
But what about Jenny’s idea, of cobbling multiple super cheap interfaces together? Well yes, that’s possible too. I’ll show you how, but first, let’s talk about how we’re going to control this software mixer monster. Yes, you can just use a mouse or keyboard, but the challenge was to build a mixing desk, and to me, that means physical faders and mute buttons. Now, there are pre-built solutions, with the Behringer X-touch being a popular solution. But again, we’re way above the price-point Jenny set for this problem. So, let’s do what we do best here at Hackaday, and build our own. Continue reading “How To Build Jenny’s Budget Mixing Desk”
Camera shutter speed is an essential adjustment in photography – along with the aperture, the shutter moderates the amount of light entering the camera. Older cameras (and some newer ones) use mechanical shutters that creep out-of-spec over the years, so [Dean Segovis] built a handy shutter speed tester.
With just a handful of basic components, this project is a great one for beginners to sink their teeth into. The tester is based around a photoresistor that measures light from another source (a flashlight) that travels through the camera body. When the shutter on the camera is released, the shutter speed can be measured and displayed on the OLED screen. An Arduino naturally handles all the computational duties. The whole thing can be easily assembled on a breadboard in just a couple of minutes.
The original project by [hiroshootsfilm] is over on Project Hub, however [Dean] takes a deeper dive with some code troubleshooting, as well as trying out a variety of old film cameras with the breadboard tester. His testing revealed that the photoresistor was better able to detect shutter speed when the camera lens was removed, which is a hot tip for anyone else that wants to try this.
While it’s not surprising that these older cameras are having trouble with their mechanical shutters, this little tester would be an invaluable tool when it comes time to start tweaking shutter mechanisms. If this project has brought out the shutterbug in you, make sure to check out this brain transplant for a Polaroid 100-series Packfilm camera that we covered way back in 2011.
Continue reading “Clock Your Camera With This Shutter Speed Tester”
If you are running video around your home theater, you probably use HDMI. If you are running it in a professional studio, however, you are probably using SDI, Serial Digital Interface. [Chris Brown] looks at SDI and shows a cheap SDI signal generator for an Arduino.
On the face of it, SDI isn’t that hard. In fact, [Chris] calls it “dead simple.” The problem is the bit rate which can be as high as 1.485 Gbps for the HD-SDI standard. Even for a super fast processor, this is a bit much, so [Chris] turned to the Arduino MKR Vidor 4000. Why? Because it has an FPGA onboard. Alas, the FPGA can’t do more than about 200 MHz, but that’s fast enough to drive an external Semtech GS296t2 serializer which is made to drive SDI signals.
The resulting project contains the Arduino, the serializer, a custom PCB, and both FPGA and microcontroller code. While the total cost of the project was a little under $200, that’s still better than the $350 to $2000 for a commercial SDI signal generator.
If you want to play along, the files are out on GitHub. We used the Vidor back in 2018 when it first came out. If you need a quick start on FPGAs, there’s always our boot camp.
As the smartphone has eaten ever more of the gatgets with which we once surrounded ourselves, it’s with some sadness that we note the calculator becoming a less common sight. It’s with pleasure then that we bring you [Nekopla]’s keychain calculator, not least because it’s a little more than a conventional model. This is a calculator which uses Reverse Polish Notation, or RPN.
A full write-up in Japanese (Google Translate link) carries an impressive level of detail about the project, but in short, it takes an Arduino Pro Micro, an array of keys, and an OLED display, and packages them on a couple of fiberglass prototyping boards in a sandwich between laser-cut Perspex front and rear panels.
The RPN notation is what makes it especially interesting,a system in which where you might be used to writing 2+2= to get 4, in RPN you would write 2 2 + . It allows the use of much simpler code with a stack-based architecture than that used in a conventional calculator. It’s a system that’s usually the preserve of some pretty exclusive machines, so it’s great to see on something with more of the toy about it.
If RPN interests you, then you might like to read our look at the subject, and even feast your eyes on the teardown of a vintage 1975 Sinclair RPN calculator.
If you’ve ever played around with macro photography, you’ve likely noticed that the higher the lens magnification, the less the depth of field. One way around this issue is to take several slices at different focus points, and then stitch the photos together digitally. As [Curious Scientist] demonstrates, this is a relatively simple motion control project and well within the reach of a garden-variety Arduino.
You can move the camera or move the subject. Either way, you really only need one axis of motion, which makes it quite simple. This build relies on a solid-looking lead screw to move a carriage up or down. An Arduino Nano acts as the brains, a stepper motor drives the lead screw, and a small display shows stats such as current progress and total distance to move.
The stepper motor uses a conventional stepper driver “stick” as you find in many 3D printers. In fact, we wondered if you couldn’t just grab a 3D printer board and modify it for this service without spinning a custom PCB. Fittingly, the example subject is another Arduino Nano. Skip ahead to 32:22 in the video below to see the final result.
We’ve seen similar projects, of course. You can build for tiny subjects. You can also adapt an existing motion control device like a CNC machine.
Continue reading “Better Macro Images With Arduino Focus Stacking”
