Animated LED Valentine Heart

With only a week left until Valentine’s day, [Henry] needed to think on his feet. He wanted to build something for his girlfriend but with limited time, he needed to work with what he had available. After scrounging up some parts and a bit of CAD work, he ended up with a nice animated LED Valentine heart.

[Henry] had a bunch of WS2812 LEDs left over from an older project. These surface mount LED’s are very cool. They come in a small form factor and include red, green, and blue LEDs all in a single package. On top of that, they have a built-in control circuit which makes each LED individually addressable. It’s similar to the LED strips we’ve seen in the past, only now the control circuit is built right into the LED.

Starting with the LEDs, [Henry] decided to build a large animated heart. Being a stickler for details, he worked out the perfect LED placement by beginning his design with three concentric heart shapes. The hearts were plotted in Excel and were then scaled until he ended up with something he liked. This final design showed where to place each LED.

The next step was to design the PCB in Altium Designer. [Henry’s] design is two-sided with large copper planes on either side. He opted to make good use of the extra copper surface by etching a custom design into the back with his girlfriend’s name. He included a space for the ATMega48 chip which would be running the animations. Finally, he sent the design off to a fab house and managed to get it back 48 hours later.

After soldering all of the components in place, [Henry] programmed up a few animations for the LEDs. He also built a custom frame to house the PCB. The frame includes a white screen that diffuses and softens the light from the LEDs. The final product looks great and is sure to win any geek’s heart. Continue reading “Animated LED Valentine Heart”

Annoy Your Enemies with the Hassler Circuit

[Craig] recently built himself a version of the “hassler” circuit as a sort of homage to Bob Widlar. If you haven’t heard of Bob Widlar, he was a key person involved in making analog IC’s a reality. We’ve actually covered the topic in-depth in the past. The hassler circuit is a simple but ingenious office prank. The idea is that the circuit emits a very high frequency tone, but only when the noise level in the room reaches a certain threshold. If your coworkers become too noisy, they will suddenly notice a ringing in their ears. When they stop talking to identify the source, the noise goes away. The desired result is to get your coworkers to shut the hell up.

[Craig] couldn’t find any published schematics for the original circuit, but he managed to build his own version with discrete components and IC’s. Sound first enters the circuit via a small electret microphone. The signal is then amplified, half-wave rectified, and run through a low pass filter. The gain from the microphone is configurable via a trim pot. A capacitor converts the output into a flat DC voltage.

The signal then gets passed to a relaxation oscillator circuit. This circuit creates a signal whose output duty cycle is dependent on the input voltage. The higher the input voltage, the longer the duty cycle, and the lower the frequency. The resulting signal is sent to a small speaker for output. The speaker is also controlled by a Schmitt trigger. This prevents the speaker from being powered until the voltage reaches a certain threshold, thus saving energy. The whole circuit is soldered together dead bug style and mounted to a copper clad board.

When the room is quiet, the input voltage is low. The output frequency is high enough that it is out of the range of human hearing. As the room slowly gets louder, the voltage increases and the output frequency lowers. Eventually it reaches the outer limits of human hearing and people in the room take notice. The video below walks step by step through the circuit. Continue reading “Annoy Your Enemies with the Hassler Circuit”

Get Better at Mortal Kombat by Hacking Your PS3 Controller

Fighting games like Mortal Kombat provide you with a variety of different available moves. These include kicks, punches, grabs, etc. They also normally include various combination moves you can perform. These combo moves require you to press the proper buttons in the correct order and also require you to time the presses correctly. [Egzola] realized that he could just hack his controller to simulate the button presses for him. This bypasses the learning curve and allows him to perform more complicated combinations with just the press of a single button.

[Egzola] started by taking apart his Playstation 3 controller. There were two PCB’s inside connected by a ribbon cable. Luckily, each individual pad for this cable was labeled with the corresponding controller button. This made it extremely simple to hack the controller. [Egzola] soldered his own wires to each of these pads. Each wire is a different color. The wires then go to two different connectors to make them easier to hook up to a bread board.

Each wire is then broken out on the breadboard. The signal from each button is run through a 4n25 optoisolator. From there the signal makes its way back to various Arduino pins. The 4n25 chips keeps the controller circuit isolated from the Arduino’s electrical circuit. The Arduino also has two push buttons connected to it. These buttons are mounted to the PS3 controller.

Now when [Egzola] presses one of the buttons, the Arduino senses the button press and simulates pressing the various controller buttons in a pre-programmed order. The result is a devastating combination move that would normally require practice and repetition to remember. You might say that [Egzola] could have spent his time just learning the moves, but that wasn’t really the point was it? Check out the video below for a demonstration. Continue reading “Get Better at Mortal Kombat by Hacking Your PS3 Controller”

A SEGA Dreamcast Controller With a Built-in Screen

[Fibbef] was hard at work on a project for a build-off competition when he accidentally fried the circuit board. Not one to give up easily, he opted to start a new project with only two days left in the competition. He managed to modify a SEGA Dreamcast controller to hold a color screen in that short amount of time.

The Dreamcast controller’s shape is somewhat conducive to this type of mod. It already has a small window to ensure the view of the visual memory card is not obstructed. Unfortunately [Fibbef’s] screen was a bit too large for this window. That meant he would have to expand the controller and the circuit board.

After taking the controller apart, he desoldered the memory card connectors. He then cut the circuit board cleanly in half vertically. He had to re-wire all of the traces back together by hand. It turned out initially that he had messed something up and accidentally fried the right half of the controller. To fix it, he cut a second controller in half and soldered the two boards together.

With some more horizontal space to work with on the PCB side of things, [Fibbef] now needed to expand the controller’s housing. He cut the controller into several pieces, making sure to keep the start button centered for aesthetics. He then used duct tape to hold popsicle sticks in place to make up for the missing pieces of the case. All of the sticks were then covered with a thick layer of ABS cement to make for a more rigid enclosure. All of this ended up being covered in Bondo, a common trick in video game console mods. It was then sanded smooth and painted with black primer to make for a surprisingly nice finish.

The screen itself still needed a way to get power and a video signal. [Fibbef] built an adapter box to take both of these signals and pass them to the controller via a single cable. The box as a USB-A connector for power input, and a composite connector for video. There’s also a USB-B connector for the output signals. [Fibbef] uses a standard printer USB cable to send power and video signals to the controller. The end result looks great and serves to make the Dreamcast slightly more portable. Check out the demo video below to see it in action. Continue reading “A SEGA Dreamcast Controller With a Built-in Screen”

PCI I-RAM Working Without a PCI Slot

[Gnif] had a recent hard drive failure in his home server. When rebuilding his RAID array, he decided to update to the ZFS file system. While researching ZFS, [Gnif] learned that the file system allows for a small USB cache disk to greatly improve his disk performance. Since USB is rather slow, [Gnif] had an idea to try to use an old i-RAM PCI card instead.

The problem was that he didn’t have any free PCI slots left in his home server. It didn’t take long for [Gnif] to realize that the PCI card was only using the PCI slot for power. All of the data transfer is actually done via a SATA cable. [Gnif] decided that he could likely get by without an actual PCI slot with just a bit of hacking.

[Gnif] desoldered a PCI socket from an old faulty motherboard, losing half of the pins in the process. Luckily, the pins he needed still remained. [Gnif] knew that DDR memory can be very power-hungry. This meant that he couldn’t only solder one wire for each of the 3v, 5v, 12v, and ground pins. He had to connect all of them in order to share the current load. All in all, this ended up being about 20 pins. He later tested the current draw and found it reached as high as 1.2 amps, confirming his earlier decision. Finally, the reset pin needed to be pulled to 3.3V in order to make the disk accessible.

All of the wires from his adapter were run to Molex connectors. This allows [Gnif] to power the device from a computer power supply. All of the connections were covered in hot glue to prevent them from wriggling lose.

A New Handle For An Old Soldering Station

About 20 years ago, [Simon] spent a few week’s pay on a soldering station, a Micron W/2172. It served him well for the past few decades, but lately he hasn’t been able to find a supply of new tips for it. The Micron went into a cupboard and he upgraded to a newer Hakko soldering station.

The old Micron was still sitting in the cupboard when [Simon] realized both stations use a 24V supply for the heater, and you can buy replacement Hakko handle for a few bucks. Having two soldering stations would be handy, so [Simon] set out to convert the old Micron station to accept Hakko handles.

The only technical challenge for this modification was to figure out how the old circuit board in the Micron would read the thermistor  in the new handle. The original circuit used a dual op-amp, with one side used to amplify the thermocouple and the other to compare it to the temperature set point. After measuring the set point and a bit of Excel, [Simon] had a small circuit board that would replace the old op-amp. After that it was only a matter of wiring the new handle into the old station, calibrating the temperature settings, and enjoying the utility of two soldering stations.

Repairing and Reviewing a 1976 PONG Clone

Hackaday alum [Todd] has been searching for an old PONG clone for the last two years. This variant is called, “The Name of the Game”. [Todd] has fond memories of playing this game with his sister when they were young. Unfortunately, being the hacker that he is, [Todd] tore the game apart when he was just 14 to build his own Commodore 64 peripherals. He’s been wanting to make it up to his sister ever since, and he finally found a copy of this game to give to his sister last Christmas.

After opening up the box, [Todd] quickly noticed something strange with the power connector. It looked a bit charred and was wiggling inside of the enclosure. This is indicative of a bad solder joint. [Todd] decided he’d better open it up and have a look before applying power to the device.

It was a good thing he did, because the power connector was barely connected at all. A simple soldering job fixed the problem. While the case was still opened, [Todd] did some sleuthing and noticed that someone else had likely made repairs to several other solder joints. He also looked for any possible short circuits, but everything else looked fine. The system ended up working perfectly the first time it was started.

The end of the video shows that even after all this time, simple games like this can still capture our attention and be fun to play for hours at a time. [Todd] is working on part 2 of this series, where he’ll do a much more in-depth review of the system. You can watch part 1 below. Continue reading “Repairing and Reviewing a 1976 PONG Clone”