Reflow Rig Makes SMD Soldering A Wok In The Park

April 25, 2018 by Dan Maloney 14 Comments

For a DIY reflow setup, most people seem to rely on the trusty thrift store toaster oven as a platform to hack. But there’s something to be said for heating the PCB directly rather than heating the surrounding air, and for that one can cruise the yard sales looking for a hot plate to convert. But an electric wok as a reflow hotplate? Sure, why not?

At the end of the day [ThomasVDD]’s reflow wok is the same as any other reflow build. It has a heat source that can be controlled easily, temperature sensors, and a microcontroller that can run the proportional-integral-derivative (PID) control algorithm needed for precise temperature control. That the heating element he used came from an electric wok was just a happy accident. A laser-cut MDF case complete with kerf-bent joints holds the heating element, the solid-state relay, and the Arduino Nano that runs the show. A MAX6675 thermocouple amp senses the temperature and allows the Nano to cycle the temperature through different profiles for different solders. It’s compact, simple, and [ThomasVDD] now has a spare wok to use on the stove top. What’s not to like?

Reflow doesn’t just mean oven or hotplate, of course. Why not give reflow headlights, a reflow blowtorch, or even a reflow work light a try?

Tracktorino Shields You From Poor Interfaces

April 21, 2018 by Brian McEvoy 8 Comments

On-screen controls in a digital audio workstation expand the power of a DJ or musician, but they are not intuitive for everyone. The tactility of buttons, knobs, sliders and real-world controls feels nothing like using a mouse, trackpad, or even a touchscreen. Unfortunately, devices meant to put control into a DJs hands can be unavailable due to location or cost. [Gustavo Silveira] took charge of the situation so he could help other DJs and musicians take control of their workstations with a customized MIDI interface for Traktor DJ software.

MIDI is a widely used serial protocol which has evolved from a DIN connector to USB, and now it is also wireless. This means that the Traktorino is not locked to Traktor despite the namesake. On the Hackaday.io page, there’s even a list of other workstations it will work with, but since many workstations, all the good ones anyway, accept MIDI hardware like this, the real list is a lot longer.

The custom circuit board is actually a shield. Using an Arduino UNO, the current poster child of the Arduino world, opens up the accessibility for many people who don’t know specialized software. A vector drawing for a lasercut enclosure is also included. This means that even the labeling on the buttons are not locked into English language.

Here’s another project which combined laser cutting and MIDI to make some very clever buttons or turn your DIN MIDI connector into USB.

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Laser Projector Ditches Galvanometer For Spinning Drum

April 20, 2018 by Ben James 25 Comments

Laser projectors like those popular in clubs or laser shows often use mirror galvanometers to reflect the laser and draw in 2D. Without galvos, and on a tight budget, [Vitaliy Mosesov] decided that instead of downgrading the quality, he would seek an entirely different solution: a spinning mirror drum.

He fires a laser at a rotating drum with twelve mirror faces, each at a different adjustable vertical angle. The laser will hit a higher or lower point on the projection surface depending on which mirror it’s reflecting off – this creates resolution in the Y direction.

Timing the pulsing of the laser so that it reflects off the mirror at a certain horizontal angle provides the X resolution.

As you can already tell, speed and timing is critical for this to work. So much so that [Vitaliy] decided he wanted to overclock his Arduino – from 16 MHz to 24.576 MHz. Since this changes the baud rate, an AVR ISP II was used for programming after the modification, and the ‘duino’s hardware serial initialization had to be hacked too.

For the laser itself, [Vitaliy] designed some nifty driver circuitry, which can respond quickly to the required >50 kHz modulation, supply high current, and filter out voltage transients on the power supply (semiconductor lasers have no protection from current spikes).

On the motor side of things, closed loop control is essential. A photo-interrupter was added to the drum for exact speed detection, as well as a differentiator to clean up the signal. Oh, and did we mention the motor is from a floppy disk drive?

We’ve actually seen builds like this before, including a dot-matrix version with multiple lasers and one made apparently out of Meccano and hot-glue that can project a Jolly Wrencher. But this build, with its multiple, adjustable mirrors, is a beauty. Check it out in action below.

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PID Control With Arduino

April 14, 2018 by Al Williams 30 Comments

Experience — or at least education — often makes a big difference to having a successful project. For example, if you didn’t think about it much, you might think it is simple to control the temperature of something that is heating. Just turn on the heater if it is cold and turn it off when you hit the right temperature, right? That is one approach — sometimes known as bang-bang — but you’ll find there a lot of issues with that approach. Best practice is to use a PID or Proportional/Integral/Derivative control. [Electronoob] has a good tutorial about how to pull this off with an Arduino. You can also see a video, below.

The demo uses a 3D printer hot end, a thermocouple, a MAX6675 that reads the thermocouple, and an Arduino. There’s also an LCD display and a FET to control the heater.

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A Hacker’s Epic Quest To Keep His Son Entertained

April 13, 2018 by Tom Nardi 22 Comments

Little humans have a knack for throwing a wrench in the priorities of their parents. As anyone who’s ever had children will tell you, there’s nothing you wouldn’t do for them. If you ever needed evidence to this effect, just take a gander at the nearly year-long saga that chronicles the construction of an activity board [Michael Teeuw] built for his son, Enzo.

Whether you start at the beginning or skip to the end to see the final product, the documentation [Michael] has done for this project is really something to behold. From the early days of the project where he was still deciding on the overall look and feel, to the final programming of the Raspberry Pi powered user interface, every step of the process has been meticulously detailed and photographed.

The construction methods utilized in this project run the gamut from basic woodworking tools for the outside wooden frame, to a laser cutter to create the graphical overlay on the device’s clear acrylic face. [Michael] even went as far as having a custom PCB made to connect up all the LEDs, switches, and buttons to the Arduino Nano by way of an MCP23017 I2C I/O expander.

Even if you aren’t looking to build an elaborate child’s toy that would make some adults jealous, there’s a wealth of first-hand information about turning an idea into a final physical device. It isn’t always easy, and things don’t necessarily go as planned, but as [Michael] clearly demonstrates: the final product is absolutely worth putting the effort in.

Seeing how many hackers are building mock spacecraft control panels for their children, we can’t help but wonder if any of them will adopt us.

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Need A Thousand Extra PWM Pins?

April 11, 2018 by Al Williams 58 Comments

If your Arduino runs out of I/O lines, you can always add one of the several I/O expander chips that takes a serial interface to set its several pins. Or perhaps you could buy something like an Arduino Mega, with its extra sockets to fulfil your needs. But what would you do if you really needed more pins, say a thousand of them? Perhaps [Brian Lough] has the answer. OK, full disclosure: If you really need a thousand, the video isn’t exactly for you, as he shows you how to add up to 992 PWM outputs. The chip he uses works with any microcontroller (the video shows an ESP8266), and we suppose you could use two daisy chains of them and break the 1,000 barrier handily.

We like how short the video is (just two minutes; see below) as it gets right to the point. The PCA9685 chip gives you 16 12-bit PWM channels via an I2C interface. You can daisy chain up to 62 of the boards to get the 992 outputs promised.

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Art Deco Radio Gets FM Reception

April 7, 2018 by Tom Nardi 12 Comments

Taking a vintage radio and cramming it full of modern, Internet-connected, guts has long been a staple of the hacking and making scene. While some might see it as a crime to take what’s arguably a legitimate piece of history and turn it into nothing more than a slipshod case for the Raspberry Pi, we have to admit there’s a certain appeal to the idea. Taking the beauty of classic design and pairing it with more modern capabilities is getting the best of both worlds.

But this project by [Nick Koumaris] is a somewhat unique take on the concept. Rather than sacrificing a real vintage piece of hardware to house the electronics, he’s designed a 3D printable case that looks like a classic 1936 AWA Radiolette. But what’s really interesting to us is that he then puts a basic FM radio inside of it.

That’s right, no Internet radio streaming or smartphone Bluetooth compatibility here. It’s just a regular FM radio, not entirely unlike the kind of hardware you’d expect to be inside of a classic radio. Of course, it’s much more modern, and [Nick] actually built it himself from a TEA5767 FM radio module and an Arduino Pro Mini.

While functionally it might not be terribly exciting, we do appreciate that he went through the trouble to make a vintage-looking user interface for the radio. While physical buttons would arguably have been more appropriate given the era, the art deco inspired font and graphics that show on the device’s Nokia 5110 LCD do look really slick.

Purists will surely be happy to see another project where a piece of vintage piece of audio equipment wasn’t sacrificed at the Altar of Hack, but we’ve also played host to many projects which weren’t nearly as concerned with historical preservation.

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