As cigar aficionados will tell you, cigars should be stored in climate controlled humidors to keep them in best condition for smoking. Most of the time a humidor is just a simple air-tight box with a hygrometer attached, which measures the relative humidity inside the box. Feeling as though he needed more control over the environment he kept his cigars in, [Justin] created the Tweetidor, a humidor that tweets its current temperature and humidity. Yes, you guessed it; the project is built around an Arduino. It’s a simple, useful project that is well documented and would be fun to recreate if you’re into cigars (and not tired of Twitter or Arduinos yet.) Combine this with the laser lighter and you’ve got a pretty nice setup.

It started with a simple need: keep tabs on SparkFun Electronics’ in-house kegerator so the beer won’t run out at inopportune times. But of course SparkFun and “simple need” make strange bedfellows…throw beer in the mix, and you know this can’t end well. The result, as you might imagine, reads like a who’s-who of electronics hackery buzzwords.

Arduino? Check. Custom PCB? Check. Web interface? Check. Twitter feed? Check.

They’ve assembled a nice build tutorial on how this all went together, including code, example circuits, an explanation of some of the sensors used, and links to other tutorials for such things as Twittering and persistent storage in EEPROM using Arduino. Not to mention the eye candy: a custom Arduino shield (solder mask and all), custom acrylic tap handle, custom SparkFun pint glasses. They never do anything halfway, do they?

[Peter] sent in this writeup on how to build a remotely accessible thermometer. The hardware side is pretty easy on this one, all you need is an Arduino, a resistor and an thermistor. The software is where the main focus is.  You can check the temperature via command line, but also via email. It can also tell you the temperature using the host computers sound hardware. You can see a video of it in action after the break. We have to wonder why he didn’t make it twitter.

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Here’s another nerdy present that was built for Valentine’s Day. [João Silva] created a temperature sensing Munny. A Munny is a vinyl toy made to be customized. Other than these Munny speakers, we haven’t seen them in many electronics projects. The LM35CZ temperature sensor has an analog output that connects to the ADC on the ATtiny15L. The microcontroller changes the RGB LED’s color based on the temperature: blue for cold, green for comfortable, and red for hot. It only flashes every three minutes to conserve the power in the coin cells. His one-off circuit board also includes an ISP header for programming. The Munny’s head looks like it does a great job diffusing the light.

Microchip’s TC74 is an inexpensive digital temperature sensor with a simple I2C interface. It has a resolution of 1 degree Celsius, and a range of -40 to +125 degrees. This is an easy way to add temperature measurement to a project without an analog to digital converter. We’ll show you how to use the TC74 below.

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Download: buspirate.v0d.zip

Dallas/Maxim’s 1-Wire protocol is the most requested addition to the Bus Pirate.  We finally got some 1-Wire parts, and today we’ll demonstrate the DS1822 1-Wire digital thermometer. Grab the datasheet (PDF) and follow along.

This post is accompanied by release v.0d of the Bus Pirate firmware for hardware version 0. This includes the new 1-Wire protocol library, more configuration options, and other improvements.

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SparkFun is rolling out interesting things to play with every week. They’ve added a NanoMuscle actuator that uses a shape memory alloy to lift nearly 70 times its own weight. Their LilyPad collection has expanded to include small momentary switches and a thermistor type temperature sensor. Lastly, they’ve got an FM receiver module. It just needs an antenna and uses I2C or SPI for control.

The dog days of Summer are looming just over the horizon like a hot sticky wave of impending doom, but you don’t have to take it lying down. Building a portable air conditioner is cheap easy, and we daresay refreshing.

You’ll need the following materials: a condenser, heater core, or radiator, a styrofoam cooler, a submersible water pump, a few case fans, some adapters to power the works, and a few other materials. The pump circulates cold water through the condenser as the fan pushes air through it and the rest of the box.

We’ve never been huge fans of swamp coolers like this one since they offer no true refrigeration cycle. What’s more, they pump a good deal of humidity into the air, which makes the heat worse in the long run, or creates a vicious cycle of cooling and humidifying. Still, when the heat is scrambling our brains, it’s hard to say no to any relief, however ephemeral.