How many times has this one happened to you? Just coming home from work, you walk in from the garage, settle down, and pick up the newspaper. But wait, did you remember to shut the garage door?
Presenting the open garage door indicator. [xjc2010] chose the simplest circuit possible, using only a switch to turn on and off the setup, an LED acting as the signal, and a transformer/resistor combo to drop the voltage to an acceptable LED friendly 2.8 volts. We don’t like how he strung wire all over his house to place the beacon, and would have…

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We love our AVR Dragon programmer. It is a small board with a lot of functionality: in-circuit serial programming, JTAG, debug wire, and high voltage serial programming. Unfortunately, out of the box it is not quite ready for action. The Dragon ships with an unpopulated prototyping area and missing a pin header for the HVSP. For most people this means soldering on pin headers and a ZIF socket then jumpering between the various programming headers and the header for the socket. Tired of working with jumper wires, [Jussi] designed a small PCB to make the connections (original link in…

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Steady fermentation temperatures, usually at about 65 degrees Fahrenheit, are an important part of brewing beer. Because of this, the wort (unfermented beer) is often temperature controlled during fermentation. [android] needed a temperature controller for fermenting beer in a chest freezer. Much like the energy efficient fridge hack from last month, the chest freezer is switched on and off to achieve the desired temperature. Instead of buying a controller, [android] built around an existing design. His project uses a solid state relay to switch an outlet on and off.
The temperature is controlled by a home thermostat. He removed…

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[Surferdude] was unhappy with the decreasing life of his aging uninterruptible power supply. He decided to beef it up using marine batteries. He extended the battery connections outside of the UPS case using #10 wire and swapped the two 12 volt gel cells with the heavy duty lead-acid batteries. Doing so upgraded the device from 20 amp-hours to 84 amp-hours at a cost of about $160. If you’re thinking about taking this on yourself, pay attention to the countinuous output rating of your UPS to prevent a fire risk.

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The tachometer or the rev counter tells how much the speed ofthe engine of the motorcycle revolutions per minute RPM.Common nowadays are electronic rev counters that can beinstalled by the dealers you get them from. But for usedmotorcycle parts, rev counters usually come in just any wrappingwithout instructions or diagrams. In cases like these, you mayinstall your rev counter with the following instructions to helpyou. The very first step is to move the headlight away. This is agreat help later on in avoiding some mistakes and willdefinitely help you finish faster. If you feel a little hesitantin removing your headlight,…

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[Megatronix] wrote in to show us this pretty crazy guitar mod. He has re wired the pickups to make the guitar a “Stereo Guitar“. Generally, the two pickup locations on a guitar are there to provide tonal variation. You can adjust the influence of each to get the sound you want. [Megatronix] decided to re wire the setup so that one is the left channel and one is the right. Thus providing actual stereo sound from his guitar. This will limit his tonal variation considerably, but should at least serve as a proof of concept. We really want to…

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Futaba makes vacuum florescent character displays that can be used as a drop-in replacement for common character LCDs. VFDs have a wider viewing angle, and generally look cooler.
Futaba’s character displays can be interfaced using the standard 8-bit or 4-bit parallel LCD interface, or a simple two-wire protocol. The protocol type is set by resistors on the back of the display, so it’s not particularly easy to change without a hot-air rework station. Today we’ll demonstrate a serially-interfaced VFD using the Bus Pirate.
Futuba VFD character LCD replacement (NA204SD02, $7.00). Datasheet (PDF).

VFD (pin #)
Bus Pirate

GND (1)…

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Maxim’s iButtons, which are small ICs in button-sized disks, are starting to show up in more and more places. They have a range of uses, from temperature loggers to identification, and all use the 1-wire protocol to communicate. Over a furrtek, they hacked an iButton used for buying things from vending machines and created an infinite money cheat. They built a small rig based on the ATmega8 to read and write data to the chip. The data was encrypted, so it wasn’t feasible to put an arbitrary amount on the card. Instead, they used a similar technique to the…

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