As a writer for Hackaday, I get to see CNC machines, Prototypers, Tesla coils, and much more on a nearly daily basis. However, there are an uncountable number of people that don’t usually get to share in these technical wonders. Maker Faires provide the chance for the public to see and interact with the inventions, kludges, and geniuses that put together the things we write about on Hackaday.
Follow along after the break for some photos of the interesting things I got to see and enjoy.
A few years back [Bunnie] took a crack at cracking the security fuses on a PIC microcontroller. Like most of the common 8-bit microcontrollers kicking around these days, the 18F1320 that he’s working with has a set of security fuses which prevent read back of the flash memory and EEPROM inside. The only way to reset those security fuses is by erasing the entire chip, which also means the data you sought in the first place would be wiped out. That is, if you were limited to using orthodox methods.
[Bunnie] had a set of the chips professionally uncapped, removing the plastic case without damaging the silicon die inside. He set to work inspecting the goodies inside with an electron microscope and managed to hammer out a rudimentary map of the layout. Turns out that flash memory can be erased with ultraviolet light, just like old EPROM chips. Microchip thought of that and placed some shielding over the security fuses to prevent them being reset in this manner. But [Bunnie] managed to do so anyway, creating an electrical tape mask to protect the rest of the data stored in the chip while bouncing UV light underneath the shielding at an angle.
Want to uncap some chips of your own without enlisting the help of others? Give this method a try.
[via Dangerous Prototypes]
[John] got a shiny new solder paste dispenser for a steal, and before he hooked up the tool, he decided to take a look inside to make sure everything was on the up and up. Aside from a few questionable wiring practices he didn’t approve of, everything else looked to be in good working order.
The only thing that was bothering [John] is that he wasn’t too keen on keeping his noisy and large air compressor in his workshop, so he set off to find a different way to provide compressed air to the device. He settled on air dusters like those used for cleaning the crumbs out of your keyboard, but he needed to find a way to reliably get the air to his solder dispenser. He heated the air can’s nozzle until he was able to screw his dispenser’s hose barb into it, creating a tight seal. The modified nozzle was reattached to the can and placed in a simple jig that keeps the nozzle held down continuously.
[John] fired up his dispenser, and the 80 psi coming from the duster was plenty to get the solder paste flowing. Sure the rig might not be the most high tech solution, but we think it’s a pretty good means of getting quiet compressed air anywhere you need it.
Most DSLR cameras have the ability to take pictures at set intervals, but sometimes the menu system can be clunky, and the options are often less than ideal. [Achim] is a big fan of time lapse photography and has been hard at work creating a hardware-based intervalometer to suit his needs. He has just finished the second revision of the controller which is just about small enough to fit inside the housing of a 2.5mm stereo plug. The timer is not 100% universal, but so far he has confirmed it works on Nikon, Canon, and Pentax cameras.
Based on a PIC10F222, the circuit’s operation is quite simple. Once the dongle is connected to your camera, you simply need to take two pictures anywhere from 0.4 seconds to 18 minutes apart. The intervalometer “watches” to see how long you waited between pictures, and proceeds to take shots at that interval until the battery dies or your memory card fills up.
As you can see in the video on his site, the timer works a treat. If you want to make one of your own, swing by his site to grab schematics and code – it’s all available for free.
*Whoops, it looks like we’ve actually covered this before. Our apologies.
As an avid gamer, [Pat Norton] uses Teamspeak with his friends when playing World of Warcraft. [Pat]’s friends were annoyed with the voice-activated option for Teamspeak and the constant squeaking of dog toys, and [Pat] was annoyed with the questionable usability of a push-to-talk key. Dissatisfied with his options, [Pat] built footswitch-controlled teamspeak button using a Teensyduino and a broken tattoo machine foot switch.
The Teensyduino is an incredibly small Arduino compatible board that was perfect for this project. Since the teensyduino can operate as a USB Human Interface Device, it’s very easy to have the board appear as another keyboard to the computer. After borrowing some code from the hardware button of a DIY photobooth, [Pat] hooked up the foot switch to two pins of the board. From there, it was very to adapt the code so the foot switch would act as a third ‘Control’ button. The results look very professional, like a factory-made game controller. We’ve seen a few foot switch keyboard devices before, and while this probably isn’t the most efficient way to have a foot switch button control something on a computer, it’s certainly the smallest we’ve seen.
[Thanh] has spent some time flying quad-copters measuring 12” motor to motor, but wanted to build something smaller so that he could fly indoors. Instead of building just one, he actually constructed five different quad-copters, with motor to motor arm spans ranging from 10” to just 3”.
In his forum post, he highlights the construction process of his 10” copter, covering each step in great detail. While he breaks down his component lists into two categories based on motor to motor span, the one common item is the TI MSP430-based controller board. In particular, he used the eZ430-RF2500 development kit, which has the added benefit of a built-in 2.4 GHz wireless radio. His quad-copter uses a Wii Motion Plus gyro board to help keep it aloft, as well a handful of other components which should be pretty familiar to most of our readers.
It’s great to see the construction broken down in such detail, we imagine it will be a great resource for anyone else looking to build their own quad-copter.
Stick around to see a quick video demonstration of his mini quad-copter in action.
[Thanks, Panikos]
A regular Hack A Day reader sent in a tip about an LM386 stero amplifier with digital volume control. The resulting build is very professional and could easily be adapted into a slick iPod dock build.
We’ve seen a few LM386-based amplifiers over the years including one that fits inside a 9V battery, but this is the first implementation of digitally controlled volume we’ve seen. The volume control of this amp uses the DS1868 dual digital pot IC in place of the usual 10K pot providing 256 steps between zero and full volume. The DS1868 is controlled by a PIC μC with a 3-wire serial connection, although this could be implemented on any microcontroller.
Although the code provided with this build outputs volume as a linear function, it would be trivial to implement a logarithmic volume output. Because the ear perceives loudness on a logarithmic scale, this would be a great way to adjust audio volume and provide a more fine-grained control. Of course this could be implemented with a logarithmic pot, but where’s the fun in that?
Check out a video of the amp after the break.
Continue reading “Stereo Amplifier With Digital Volume Control”
