Generate Electricity With A Candle

What you see above is a generator that converts heat to electricity. [Reukpower’s] thermoelectric lamp is one of those hacks that makes you scratch your head even though you understand why it should work. The heart of the system uses a Peltier cool, just like the thermoelectric solar generator. When there is a temperature differential from one side of the Peltier to the other a small current is generated.

In this case a candle heats one side and a heat sink cools the other. The tiny voltage picked up from the Peltier’s contacts is then boosted using a joule thief. We’ve seen LEDs powered with a joule thief before, benefiting from their own low power consumption. In this case, the boost circuit is scavenged from an emergency phone charger and probably achieves higher efficiency than if he had built it himself.

Record Player Display Sans POV

At first glance we thought this record player had been modified to serve as a persistence of vision device. The device looks very much like an unmodified turntable but it has four tracks worth of display space in it. The messages are actually glowing and don’t depend on a POV effect. Instead, the table has been coated with phosphorescent paint that will glow after being exposed to bright light. The needle has been replaced by a small PCB with downward facing LEDs on it. A microcontroller pulses the lights to expose the paint in patterns that make up the messages. This is the same concept we saw with the Ghost Matrix but this iteration is silent, and the control circuitry is less apparent.

The video after the break is a must-watch. The 60 character long messages are beautiful to watch rotate into the display. Unlike a POV display, ambient light will greatly interfere with the effectiveness of this method. That being said, what a wonderful party decoration this would be if mounted on a wall in a rather dark room.

Continue reading “Record Player Display Sans POV”

NES RAM Replacement

[Spatula Tzar] Turned on her NES one day to find it no longer working. Off went the case and out came the oscilloscope. After probing around for a bit, she found that one of the RAM chips was very hot. She hot aired off the bad chip implementing an “Impenetrable Aluminum Heat Shield of Science” to protect the rest of the components. In the chip’s place she soldered a wide DIP socket for which the NES engineers had thoughtfully left a place. Then, using a 128Mbit SRAM SOIC, she soldered it to 0.100″ headers to fit in the socket. As the original chip was only 16Mbit, unused address lines are tied high or low. The console is now fully functional again. Also checkout the comments on Oldschool NES ‘repair’ how-to.

TOBI The Tool Bot

[youtube=http://www.youtube.com/watch?v=ChmDJ7RSZYE]

[TheGrue] has put together this great writeup on how he built TOBI, the tool carrying robot. Inspired by a story he read about a robot that could follow people around, using heat sensors, he decided he wanted to do something similar. His robot would carry his tools, in this case, the tools of an IT professional. Not only would it carry his tools, but surely it would give him credit as a techno-guru to have a scratch built robot following him around.

His build process is documented quite well. He approached this in a fashion where he set several iterations. Each step would add a feature and carry the old features forward. It looks as if he’s currently working on step 3, which means that the chassis has already been built, the drive train is working, it can be remote controlled, and now has some level of autonomy thanks to a propeller controller. Up next are some range finders and an assortment of other sensors so that TOBI won’t drive off any steps, or into any walls.

[via hackedgadgets]

BT Phone Is Much More Than Retrofit

[Santiago] turned his Ericfon into a Bluetooth phone. This is completely different from the handset retrofits we looked at last month. This is because he didn’t simply crack open a BT headset and cram it into his phone. He developed his own hardware for full functionality.

This is an open source project with available hardware details that he intends to turn into a kit. [Santiago] has purposed a PIC microcontroller to connect with a WT32 bluetooth module. The PIC allows for a dial tone, dialing with the original rotary dial, and produces the original sound when the phone rings. What he now has is a way to have a home phone without a landline. As seen the video after the break, the Ericfon works the same as it did when it was new, except the connection is made through Bluetooth and not via a copper phone line. Continue reading “BT Phone Is Much More Than Retrofit”

FPGA Keyboard Synthesizer

This synthesizer relies solely on an FPGA for key detection and sound synthesis. [Chris] and [Joe] built it for their final project at Cornell. The hardware implementation includes velocity sensing for the keys. While at rest, each key contacts a strip of copper foil. A matching strip of foil contacts the key when it is depressed. The velocity data is extrapolated by detecting when a key leaves the rest state and arrives at the depressed state. Sound synthesis is handled in hardware using the Karplus-Strong string synthesis method.  If you want to hear what it sounds like, they’ve posted a video (MP4) that shows off the creation. It sounds like an electric piano to us, so mission accomplished.

Pinball Build Throws Down The Gauntlet

[Jeri Ellsworth] is building her own pinball machine. Her build log is delivered in the form of daily videos that walk through the progress. In addition to seeing the intricate ramps, traps, and controllers she outlines her build techniques. These include reproducing parts based on old pinball machines and bending acrylic with a custom tool or a toaster oven.

The driver she’s planning to use is an Altera FPGA with a bunch of FETs to control the heavy-load components. There’s not a ton of info on the actual electronics but we had a heck of a fun time looking at the creative field components. Our favorite by far is the television from Day 7. The screen is translucent with a rear projected image. When the ramp in front of it is raised the pinball can be jumped right through the screen!

We couldn’t find a project page for this but we’ve embedded [Jeri’s] videos after the break. Continue reading “Pinball Build Throws Down The Gauntlet”